May 2025 Patch Tuesday: Five Zero-Days Unleashed & Critical Flaws Demand Action!

Alright folks, buckle up. Microsoft’s May 2025 Patch Tuesday has landed, and it’s a doozy. We’re looking at a hefty 72 vulnerabilities squashed, but the real headline grabbers are the five actively exploited zero-day vulnerabilities already making waves in the wild. If that wasn’t enough to make you sit up, there are also two publicly disclosed zero-days and a handful of “Critical” rated bugs demanding your immediate attention. Let’s break down what you need to know and, more importantly, what you need to do.

I. The TL;DR: Top Threats & Your Action Plan

1. What’s Keeping Security Teams Up at Night?

This month’s patch batch is serious business. Those five zero-days being actively exploited? We’re talking:

• CVE-2025-30400 (DWM Core Library)
• CVE-2025-32701 (CLFS Driver)
• CVE-2025-32706 (CLFS Driver)
• CVE-2025-32709 (WinSock AFD)
• CVE-2025-30397 (Scripting Engine)

Most of these are Elevation of Privilege (EoP) nasties, meaning once an attacker gets a foot in the door, these bugs are their golden ticket to SYSTEM or admin-level control. Think of them as the second punch in a combo attack. One of the zero-days, the Scripting Engine flaw (CVE-2025-30397), is a Remote Code Execution (RCE) vulnerability, though it does need a user to click a dodgy link.

Beyond the zero-days already in play, two others had their details splashed online before a fix was ready (CVE-2025-26685 and CVE-2025-32702), basically giving attackers a head start. And let’s not forget the six “Critical” vulnerabilities, five of which are RCEs – big, flashing red lights for your remote attack surface.

We’re seeing a pattern here: core Windows components like the Common Log File System (CLFS) Driver, Desktop Window Manager (DWM), and WinSock are recurring targets. The fact that five zero-days are being exploited right now tells you how fast the bad guys are moving. That window between a vulnerability dropping and it being used in attacks? It’s shrinking. Fast.

1. Your Hit List: Prioritized Patching & Defense

No time to waste. Here’s your game plan:

1. Patch NOW (Zero-Days): Those five actively exploited zero-days? Top of the list. No excuses.
2. Patch ASAP (Publicly Disclosed): The two publicly disclosed zero-days are next. Attackers know about them, so consider them armed and dangerous.
3. Critical Next: All “Critical” vulnerabilities, especially the RCEs, need to be tackled with urgency.
4. Sharpen Your Senses (Detection & Response): Microsoft hasn’t exactly handed out a playbook (Indicators of Compromise, or IoCs) for these zero-days. That means your Endpoint Detection and Response (EDR) needs to be on point. Look for weird behavior – unusual processes grabbing SYSTEM rights, or browsers suddenly executing strange scripts.
5. Sector-Specific Scrutiny: all Industries running Legacy systems, medical devices (IoMT), and cloud services could all be in the firing line.

1. Briefing Your Boss: Key Takeaways

Need to get the C-suite up to speed? Here’s the short version:

• Top Threats: Five zero-days are being actively exploited (CVE-2025-30400, CVE-2025-32701, CVE-2025-32706, CVE-2025-32709, CVE-2025-30397). Two more were publicly known before fixes (CVE-2025-26685, CVE-2025-32702).
• Defense Plan: Patching is priority one. Beef up endpoint monitoring for unusual activity. Train users to spot sketchy links (especially for CVE-2025-30397).
• The Bigger Picture: These EoP bugs show that attackers are good at getting in. Strong internal security, like network segmentation and least privilege, is just as vital as keeping the perimeter locked down.

Table 1: Prioritized Action Summary for Key Vulnerabilities (May 2025)

CVE ID	Vulnerability Name	CVSS v3.1 Score	Overall Risk	Recommended Action
CVE-2025-30400	Microsoft DWM Core Library Elevation of Privilege Vulnerability	7.8 HIGH	CRITICAL (Actively Exploited)	Patch Immediately. Monitor for anomalous DWM behavior and unexpected SYSTEM privilege escalation.
CVE-2025-32701	Windows Common Log File System Driver Elevation of Privilege Vulnerability	7.8 HIGH	CRITICAL (Actively Exploited)	Patch Immediately. Monitor CLFS interactions (clfs.sys) and associated TTPs (e.g., certutil downloads, LSASS dumping).
CVE-2025-32706	Windows Common Log File System Driver Elevation of Privilege Vulnerability	7.8 HIGH	CRITICAL (Actively Exploited)	Patch Immediately. Monitor CLFS interactions and for exploitation of improper input validation.
CVE-2025-32709	Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability	7.8 HIGH	CRITICAL (Actively Exploited)	Patch Immediately. Monitor afd.sys behavior and network-related processes gaining SYSTEM rights.
CVE-2025-30397	Scripting Engine Memory Corruption Vulnerability	7.5 HIGH	CRITICAL (Actively Exploited)	Patch Immediately. Minimize IE Mode use. Enhance user training on suspicious links. Monitor browser processes for suspicious script execution.
CVE-2025-26685	Microsoft Defender for Identity Spoofing Vulnerability	6.5 MEDIUM	HIGH (Publicly Disclosed)	Patch Promptly. Monitor Defender for Identity logs for anomalous authentications. Segment network to limit sensor exposure.
CVE-2025-32702	Visual Studio Remote Code Execution Vulnerability	7.8 HIGH	HIGH (Publicly Disclosed)	Patch Promptly. Train developers on safe project handling. Monitor Visual Studio processes for suspicious activity.
CVE-2025-29967	Remote Desktop Client Remote Code Execution Vulnerability	8.8 HIGH	HIGH (Critical RCE)	Patch Promptly. Restrict outbound RDP. Train users on connecting only to trusted RDP servers. Monitor mstsc.exe activity.
CVE-2025-30377	Microsoft Office Remote Code Execution Vulnerability	Critical	HIGH (Critical RCE)	Patch Promptly. Employ email/web security for malicious documents. User training. Monitor Office app behavior.
CVE-2025-47732	Microsoft Dataverse Remote Code Execution Vulnerability	8.7 HIGH	HIGH (Critical RCE in Cloud Service)	Monitor Microsoft advisories for service-side patching. Review custom app security interacting with Dataverse. Monitor Dataverse audit logs.

II. May 2025 Patch Tuesday: The Full Monty

1. The Numbers Game: 72 Flaws Fixed

Microsoft dropped fixes for 72 vulnerabilities this month. And that’s not counting the ones in Azure, Dataverse, Mariner, and Microsoft Edge that got patched earlier. Here’s how the main batch breaks down:

• Elevation of Privilege (EoP): 17
• Security Feature Bypass: 2
• Remote Code Execution (RCE): 28
• Information Disclosure: 15
• Denial of Service (DoS): 7
• Spoofing: 2

Notice a theme? EoP and RCE vulnerabilities make up a whopping 62.5% of the fixes. All five actively exploited zero-days? Yep, EoP or RCE. Five of the six criticals? RCE. Attackers love these types of flaws because they either get them in the door (RCE) or give them the keys to the kingdom once they’re inside (EoP). It’s a potent one-two punch.

1. Zero-Days in the Wild: The “Exploitation Detected” Crew

These are the five troublemakers confirmed to be actively exploited before patches were out:

• CVE-2025-30400: Microsoft DWM Core Library Elevation of Privilege Vulnerability
• CVE-2025-32701: Windows Common Log File System Driver Elevation of Privilege Vulnerability
• CVE-2025-32706: Windows Common Log File System Driver Elevation of Privilege Vulnerability
• CVE-2025-32709: Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
• CVE-2025-30397: Scripting Engine Memory Corruption Vulnerability

1. Publicly Known, Now Patched: The “Heads Up” Zero-Days

Two more vulnerabilities had their dirty laundry aired in public before fixes arrived, giving attackers a nice, long look:

• CVE-2025-26685: Microsoft Defender for Identity Spoofing Vulnerability
• CVE-2025-32702: Visual Studio Remote Code Execution Vulnerability

1. The “Critical” List: Don’t Ignore These

Six vulnerabilities earned the “Critical” badge. Five are RCEs, one’s an Info Disclosure. Here’s the rogues’ gallery:

• CVE-2025-33072: Microsoft msagsfeedback.azurewebsites.net Information Disclosure Vulnerability (Azure)
• CVE-2025-29827: Azure Automation Elevation of Privilege Vulnerability
• CVE-2025-29813: Azure DevOps Server Elevation of Privilege Vulnerability
• CVE-2025-29972: Azure Storage Resource Provider Spoofing Vulnerability
• CVE-2025-47732: Microsoft Dataverse Remote Code Execution Vulnerability
• CVE-2025-30377: Microsoft Office Remote Code Execution Vulnerability
• CVE-2025-30386: Microsoft Office Remote Code Execution Vulnerability
• CVE-2025-47733: Microsoft Power Apps Information Disclosure Vulnerability
• CVE-2025-29967: Remote Desktop Client Remote Code Execution Vulnerability
• CVE-2025-29833: Microsoft Virtual Machine Bus (VMBus) Remote Code Execution Vulnerability
• CVE-2025-29966: Remote Desktop Client Remote Code Execution Vulnerability
• And a quartet of Windows Media RCEs: CVE-2025-29964, CVE-2025-29840, CVE-2025-29962, CVE-2025-29963.

This isn’t just a Microsoft problem, either. Apple, Cisco, Fortinet, Google, Intel, SAP, and SonicWall all pushed out updates in May. Patch Tuesday is a massive, recurring fire drill for IT teams. You need a smart, risk-based game plan to keep up.

III. Deep Dive: The Actively Exploited Zero-Days – What You’re Up Against

Microsoft’s May 2025 Patch Tuesday is a stark reminder: zero-days are out there, and attackers are using them. Five of these are already being exploited. The kicker? Microsoft isn’t sharing specifics on how they’re being used or giving us IoCs. That means patching fast and smart detection are your best bets.

Table 2: Overview of Actively Exploited Zero-Day Vulnerabilities (May 2025)

CVE ID	Vulnerability Name	CVSS v3.1 Score & Vector	Vulnerability Type	Brief Description (Source: Microsoft Advisory Snippets)	Key Impact
CVE-2025-30400	Microsoft DWM Core Library Elevation of Privilege Vulnerability	7.8 HIGH AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Elevation of Privilege (Use-After-Free)	“Use after free in Windows DWM allows an authorized attacker to elevate privileges locally.”	Attacker gains SYSTEM privileges.
CVE-2025-32701	Windows Common Log File System Driver Elevation of Privilege Vulnerability	7.8 HIGH AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Elevation of Privilege (Use-After-Free)	“Use after free in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally.”	Attacker gains SYSTEM privileges.
CVE-2025-32706	Windows Common Log File System Driver Elevation of Privilege Vulnerability	7.8 HIGH AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Elevation of Privilege (Improper Input Validation)	“Improper input validation in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally.”	Attacker gains SYSTEM privileges.
CVE-2025-32709	Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability	7.8 HIGH AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Elevation of Privilege (Use-After-Free)	“Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.”	Attacker gains SYSTEM privileges. (Some sources say Administrator)
CVE-2025-30397	Scripting Engine Memory Corruption Vulnerability	7.5 HIGH AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H	Remote Code Execution (Type Confusion)	“Access of resource using incompatible type (‘type confusion’) in Microsoft Scripting Engine allows an unauthorized attacker to execute code over a network.”	Unauthenticated attacker gains RCE via browser (IE Mode) by tricking authenticated user.

2. CVE-2025-30400 – Microsoft DWM Core Library EoP: From User to SYSTEM

• 1. The Nitty-Gritty:
  This baddie, CVE-2025-30400, is a Use-After-Free (UAF) flaw in the Windows Desktop Window Manager (DWM) Core Library (dwmcore.dll). If an attacker is already on your system with standard user rights, this bug lets them climb the ladder to full SYSTEM privileges. Think total control. DWM is everywhere – Windows 10, Windows 11 (multiple versions), Server 2022, and Server 2025. That’s a lot of potential targets. It’s rated 7.8 (High) on the CVSS scale.
• 2. How Attackers Use It (MITRE ATT&CK Style):
  This is classic Privilege Escalation (TA0004), specifically Exploitation for Privilege Escalation (T1068). The weakness itself is Use After Free (CWE-416) – basically, the system tries to use memory it already threw away, and attackers can hijack that moment.
• 3. The Real-World Risk:
  Picture this: attacker gets in via a phishing email or another RCE. They’re a standard user. Then, they run their exploit for CVE-2025-30400. Boom – they’re SYSTEM. No extra clicks needed from the user at this stage. They just need that initial local access and low privileges.
• 4. The Domino Effect (Attack Chain):
  EoP bugs like this are rarely solo acts. They’re the crucial middle step. Attacker gets in (RCE), escalates (CVE-2025-30400), then owns your system. They can disable security, steal data, install backdoors, or drop ransomware. With SYSTEM rights, moving to other machines on your network is child’s play. Microsoft says it’s being exploited, but they’re tight-lipped on the exact “how.”
• 5. Your Defense Playbook:

• Patch, Patch, Patch: Get the May 2025 updates deployed. Stat. Think KBs like KB5058411, KB5058405 (Win 11), and KB5058379 (Win 10).
• Beyond Patching:

• EDR is Your Friend: Look for weird DWM behavior or processes suddenly getting SYSTEM rights.
• Least Privilege, Always: Users and apps should only have the permissions they absolutely need.
• Application Control: Whitelisting can stop unknown exploit payloads in their tracks.

• Endpoint Monitoring: Keep an eye on dwm.exe. Watch for unusual child processes or post-EoP activities like LSASS dumping.
• User Training: Doesn’t stop this specific EoP, but it helps prevent the initial break-in.

The fact that we’re seeing so many Use-After-Free bugs in critical Windows bits like DWM, CLFS, and WinSock – all leading to SYSTEM and all actively exploited – is a huge red flag. Memory safety is a tough nut to crack for Windows. These components are deep-seated, and flaws here are gold for attackers. The sheer number of these being exploited at once means bad guys are getting really good at finding and weaponizing them. This makes patching and good EDR non-negotiable. It also screams that attackers are acing the post-compromise game. They get in, then they level up. Defense-in-depth is key.

1. CVE-2025-32701 – Windows CLFS Driver EoP: Another Path to SYSTEM

• 1. The Nitty-Gritty:
  CVE-2025-32701 is another Use-After-Free (UAF) vulnerability, this time in the Windows Common Log File System (CLFS) Driver (clfs.sys). Just like the DWM flaw, if an attacker has local access, they can use this to become SYSTEM. CLFS is a core logging service used all over Windows, so its reach is massive. CVSS score: 7.8 (High).
• 2. How Attackers Use It (MITRE ATT&CK Style):
  Again, it’s Privilege Escalation (TA0004) via Exploitation for Privilege Escalation (T1068). The weakness is Use After Free (CWE-416).
• 3. The Real-World Risk:
  Same story, different component. Attacker gets in, has standard rights, runs their CLFS exploit, and bingo – SYSTEM access. Ransomware gangs love CLFS bugs for this exact reason before they deploy their main payload. It’s local, needs no extra user clicks, and only requires low initial privileges.
• 4. The Domino Effect (Attack Chain):
  This is a ransomware operator’s dream. Phish user -> Get RCE -> Exploit CVE-2025-32701 for SYSTEM -> Disable security, encrypt everything, steal data. Full system pwnage. From there, they can spread across your network and set up shop permanently. It’s actively exploited, but no specific IoCs from Microsoft. We know past CLFS exploits involved tools like PipeMagic.
• 5. Your Defense Playbook:

• Patch It: May 2025 updates are your first line of defense.
• Beyond Patching: EDR, Least Privilege, Application Control. Microsoft is reportedly testing HMAC integrity checks for CLFS logs, which could be a future structural fix.
• Endpoint Monitoring: Watch clfs.sys like a hawk. Look for weird interactions or processes behaving strangely after touching CLFS. Think about TTPs from past CLFS attacks: certutil.exe downloading nasty files, or procdump.exe trying to dump LSASS.
• User Training: Stop that initial phish!

CLFS is becoming a real headache – a recurring nightmare of actively exploited zero-days. This Patch Tuesday has two of them. Microsoft has patched dozens of CLFS bugs since 2022, but attackers, especially ransomware crews, keep finding new ways in. This makes CLFS a top-priority patching target and a critical component to monitor. Even without specific IoCs for this zero-day, look at past attacks. Groups like Storm-2460 (using PipeMagic) and Play ransomware have hit CLFS hard. Their tactics (like using certutil or procdump) are good general indicators to hunt for.

1. CVE-2025-32706 – Windows CLFS Driver EoP (Again!): Improper Input Validation Route

• 1. The Nitty-Gritty:
  Yes, another CLFS Driver EoP, CVE-2025-32706. But this one’s different: it’s due to Improper Input Validation, not a UAF. Still gets an attacker to SYSTEM privileges if they’re already on the box. Kudos to Benoit Sevens (Google Threat Intelligence) and the CrowdStrike Advanced Research Team for finding this one. CVSS score: 7.8 (High). Widespread impact, as CLFS is fundamental.
• 2. How Attackers Use It (MITRE ATT&CK Style):
  Privilege Escalation (TA0004) through Exploitation for Privilege Escalation (T1068). The weakness here is Improper Input Validation (CWE-20) – the software doesn’t check its inputs properly, and attackers can send crafted data to cause trouble.
• 3. The Real-World Risk:
  Attacker with low-privilege local access feeds CLFS some bad data, exploits the validation flaw, and becomes SYSTEM. Local exploit, no user clicks needed, low initial privileges required.
• 4. The Domino Effect (Attack Chain):
  Just like its UAF cousin (CVE-2025-32701), this is a post-RCE tool for full system control. Ransomware, data theft, persistence, lateral movement – all on the table. Actively exploited, but again, Microsoft is quiet on the specifics.
• 5. Your Defense Playbook:

• Patch It (Seriously, CLFS!): May 2025 updates.
• Beyond Patching: EDR, Least Privilege, Application Control.
• Endpoint Monitoring: Monitor clfs.sys interactions. Since it’s an input validation bug, advanced EDRs might spot weirdly crafted inputs to CLFS functions, but that’s a tough ask for most.
• User Training: Prevent that initial foothold.

Two different types of actively exploited bugs in CLFS in one month (UAF and Improper Input Validation) is a big deal. It means CLFS might have deeper, systemic issues. Attackers are clearly poking it from all angles. For defenders, this means patch all CLFS vulnerabilities, no matter the type, ASAP. The fact that external researchers found this one also shows how vital the whole security community is in this fight.

1. CVE-2025-32709 – Windows WinSock AFD EoP: Network Driver in the Crosshairs

• 1. The Nitty-Gritty:
  CVE-2025-32709 is a Use-After-Free (UAF) in the Windows Ancillary Function Driver (AFD) for WinSock (afd.sys). This kernel-mode driver is key for Windows networking. A local attacker can use this to get SYSTEM privileges. Disclosed by an “Anonymous” researcher. CVSS score: 7.8 (High). Affects pretty much all Windows systems due to WinSock’s ubiquity.
• 2. How Attackers Use It (MITRE ATT&CK Style):
  Privilege Escalation (TA0004) via Exploitation for Privilege Escalation (T1068). Weakness: Use After Free (CWE-416).
• 3. The Real-World Risk:
  Attacker with initial low-privilege access exploits the UAF in afd.sys and gets SYSTEM. Local attack, no extra user clicks needed. Microsoft says SYSTEM, some others say Administrator – either way, it’s bad.
• 4. The Domino Effect (Attack Chain):
  Standard EoP playbook: chain it after an RCE for full system pwnage. Disable security, steal data, install backdoors, move laterally. Actively exploited. No specific public IoCs from Microsoft.
• 5. Your Defense Playbook:

• Patch It: May 2025 updates.
• Beyond Patching: EDR, Least Privilege, Application Control.
• Endpoint Monitoring: Watch afd.sys behavior. Look for network-related processes suddenly getting SYSTEM rights. Past AFD exploits (like CVE-2023-21768) involved user-mode apps passing bad pointers to the driver, so monitoring API calls to afd.sys with weird parameters could be a detection angle (if your tools are up to it).
• User Training: Stop the initial breach.

This one, along with the DWM and CLFS flaws, shows a clear trend: kernel-level drivers are hot targets for attackers aiming for full SYSTEM control. These drivers are complex and have a huge attack surface. The “Anonymous” disclosure also shows that critical bug info can come from anywhere. Stay vigilant and consume threat intel broadly.

1. CVE-2025-30397 – Scripting Engine RCE: Old Browser Tech Bites Back

• 1. The Nitty-Gritty:
  CVE-2025-30397 is a memory corruption bug (specifically, “type confusion”) in the Microsoft Scripting Engine. This one’s an RCE, but there’s a catch: an attacker needs to trick an authenticated user into clicking a special link that opens in either Internet Explorer or Microsoft Edge running in IE Mode. CVSS 7.5 (High), but attack complexity is high and user interaction is required. This mainly hits orgs still using IE Mode for legacy apps.
• 2. How Attackers Use It (MITRE ATT&CK Style):
  Execution (TA0002), possibly Initial Access (TA0001). The technique is Exploitation for Client Execution (T1203). If it’s via a phishing link, then Spearphishing Link (T1566.001) is in play. The weakness is Access of Resource Using Incompatible Type (‘Type Confusion’) (CWE-843) – the program gets confused about what type of data it’s handling.
• 3. The Real-World Risk:
  Attacker crafts a malicious webpage or email link. User clicks, it opens in IE or IE Mode, and the type confusion bug triggers RCE in the user’s context. No prior attacker privileges needed, but user interaction is key. If the user is an admin, game over. If not, this is step one for the attacker.
• 4. The Domino Effect (Attack Chain):
  If this RCE gets standard user rights, attackers will chain it with an EoP bug (like the other four zero-days this month!) to get SYSTEM. Full compromise, data theft, ransomware, persistence – the usual horror show. Actively exploited. Check Point has an IPS signature for this one.
• 5. Your Defense Playbook:

• Patch It: May 2025 updates.
• Beyond Patching:

• Ditch IE Mode (If You Can): Seriously reduce or kill IE Mode. Use Enterprise Mode Site Lists to lock it down to only essential legacy apps.
• User Training (Crucial Here!): Teach users to spot and avoid suspicious links. This is your best defense against this specific bug.
• Web/Email Security: Filter out malicious sites and emails.
• EDR: Look for weird script execution from browsers (especially iexplore.exe or msedge.exe in IE mode).

• IDS/IPS Rules: Check Point has “Microsoft Scripting Engine Memory Corruption (CVE-2025-30397)”. Others may follow.
• Endpoint Monitoring: Watch processes spawned by browsers, especially if IE Mode is in play.

This zero-day is a painful reminder: legacy tech, even when “emulated” like IE Mode, is a persistent risk. Attackers know this and are targeting it. It also shows that even with zero-days, social engineering (getting that click) is still a go-to tactic. So, technical fixes and user awareness are both critical.

IV. The Publicly Known Crew: CVE-2025-26685 & CVE-2025-32702

Two more zero-days were out in the open before Microsoft patched them. This early exposure means more eyes on the flaws and a higher chance of exploits popping up, even if they weren’t actively used at disclosure.

Table 3: Overview of Publicly Disclosed Zero-Day Vulnerabilities (May 2025)

CVE ID	Vulnerability Name	CVSS v3.1 Score & Vector	Vulnerability Type	Brief Description (Source: Microsoft Advisory Snippets)	Key Impact
CVE-2025-26685	Microsoft Defender for Identity Spoofing Vulnerability	6.5 MEDIUM AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N	Spoofing (Improper Authentication)	“Improper authentication in Microsoft Defender for Identity allows an unauthorized attacker to perform spoofing over an adjacent network.”	Unauthenticated attacker with LAN access can spoof another account, impacting confidentiality.
CVE-2025-32702	Visual Studio Remote Code Execution Vulnerability	7.8 HIGH AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	Remote Code Execution (Command Injection)	“Improper neutralization of special elements used in a command (‘command injection’) in Visual Studio allows an unauthorized attacker to execute code locally.”	Unauthenticated attacker can achieve local RCE by tricking user into opening malicious content.

1. CVE-2025-26685 – Microsoft Defender for Identity Spoofing: Trust Betrayed?

• 1. The Nitty-Gritty:
  This one, CVE-2025-26685, is an improper authentication flaw in Microsoft Defender for Identity. It lets an unauthenticated attacker on your local network (LAN) spoof another account. Defender for Identity is supposed to stop compromised identities, so a bug here is ironic and worrying. Kudos to Joshua Murrell with NetSPI for the find. It’s a CVSS 6.5 (Medium), mainly hitting confidentiality because an attacker could impersonate someone to access info.
• 2. How Attackers Use It (MITRE ATT&CK Style):
  This falls under Credential Access (TA0006) or Defense Evasion (TA0005). If they spoof a legit account, it’s like using Valid Accounts (T1078). The core weakness is Improper Authentication (CWE-287).
• 3. The Real-World Risk:
  An attacker needs to be on your LAN. From there, they exploit the bad authentication in a Defender for Identity sensor and pretend to be someone else. No user clicks, no prior privileges needed by the attacker. The danger depends on who they can spoof. A regular user? Bad. An admin? Very bad.
• 4. The Domino Effect (Attack Chain):
  If an attacker is already inside your network, this could be their ticket to specific resources or more intel. Spoofing a privileged account could lead to lateral movement or further escalation. While not actively exploited (yet), public disclosure means PoCs could be on their way.
• 5. Your Defense Playbook:

• Patch It: May 2025 updates.
• Beyond Patching:

• Network Segmentation: Make it harder for attackers to get “adjacent network access” to your Defender for Identity sensors and domain controllers.
• Log Monitoring: Watch Defender for Identity logs for weird authentications or access patterns.
• Strong Authentication Everywhere: Minimize the blast radius if one account gets spoofed.

• IDS/IPS Rules: Vendors might release signatures if more technical details emerge.
• Endpoint Monitoring: Focus on Defender for Identity sensor logs and DC logs.

Bugs in security products are always a gut punch. These are the tools we trust! An attacker exploiting Defender for Identity could operate stealthily or even use its own privileges against you. The “Adjacent Network” attack vector means they need to be inside first, but one phished workstation can be enough. Zero-trust principles, even for your security gear, are crucial.

1. CVE-2025-32702 – Visual Studio RCE: Developer Machines in Danger

• 1. The Nitty-Gritty:
  CVE-2025-32702 is an RCE in Visual Studio due to a command injection flaw. An unauthenticated attacker can run code on a developer’s machine if they trick the dev into opening a malicious file or project in Visual Studio. CVSS 7.8 (High). This is a direct threat to anyone using vulnerable Visual Studio versions.
• 2. How Attackers Use It (MITRE ATT&CK Style):
  This is Execution (TA0002). Specifically, Exploitation for Client Execution (T1203) or using a Command and Scripting Interpreter (T1059) because the injected commands often run via a shell. The weakness is Improper Neutralization of Special Elements used in a Command (‘Command Injection’) (CWE-77) – the software doesn’t clean up special characters in commands, letting attackers sneak in their own.
• 3. The Real-World Risk:
  Attacker crafts a malicious Visual Studio project or file. They send it to a developer (phishing, dodgy repo, fake download). Developer opens it. Boom – attacker’s code runs with the developer’s privileges. The attacker doesn’t need prior access to create the file, but the dev needs to interact with it.
• 4. The Domino Effect (Attack Chain):
  This can be an initial access vector. If the dev is a standard user, the attacker then looks for an EoP. If the dev runs VS as admin (bad idea!), it’s instant full compromise. Developer machines are goldmines: source code, API keys, internal creds, CI/CD access. Pwning a dev box can lead to supply chain attacks or deep network infiltration. Public disclosure means PoCs are likely.
• 5. Your Defense Playbook:

• Patch It: May 2025 Visual Studio updates.
• Beyond Patching:

• User Awareness (for Devs!): Train developers: DON’T open VS projects/files from untrusted sources.
• Least Privilege for Devs: Run VS as a standard user unless absolutely necessary.
• EDR: Watch for devenv.exe (Visual Studio) spawning suspicious processes or using weird command lines.

• Endpoint Monitoring: Monitor processes launched by devenv.exe. Look for unexpected shells (cmd.exe, powershell.exe) or VS trying to access things it shouldn’t.

Bugs in dev tools like Visual Studio are a fast track to an organization’s crown jewels. This public disclosure of a command injection flaw puts it on every attacker’s radar, especially those interested in corporate espionage or supply chain hits. Remember, even though it’s “local” execution, the attack starts with tricking a user. User awareness is key, even for your tech-savvy devs.

V. Critical Chaos: The Other Heavy Hitters (Beyond Zero-Days)

Beyond the zero-days causing immediate panic, May’s Patch Tuesday also tackles several other “Critical” vulnerabilities. These are predominantly Remote Code Execution (RCE) flaws, and they absolutely demand your swift attention to prevent attackers from waltzing into your systems.

Table 4: Selected Critical Vulnerabilities (May 2025)

CVE ID	Vulnerability Name	CVSS v3.1 Score & Vector	Vulnerability Type	Brief Description	Potential Impact
CVE-2025-29967	Remote Desktop Client Remote Code Execution Vulnerability	8.8 HIGH AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	Remote Code Execution (Heap-based Buffer Overflow)	Heap-based buffer overflow in RDP Client. Attacker-controlled server can execute code on client connecting to it.	RCE on client machine with user’s privileges when connecting to malicious RDP server.
CVE-2025-30377	Microsoft Office Remote Code Execution Vulnerability	Critical (CVSS not specified in snippets)	Remote Code Execution	RCE in Microsoft Office. Likely triggered by opening a malicious document.	RCE with user’s privileges upon opening a malicious Office file.
CVE-2025-30386	Microsoft Office Remote Code Execution Vulnerability	8.4 HIGH AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	Remote Code Execution (Use-After-Free)	Use-after-free in Microsoft Office allows local code execution. (UI:N in NVD, but Office RCEs typically UI:R via file opening)	RCE with user’s privileges, potentially locally if UI:N is accurate, or via file opening if UI:R.
CVE-2025-47732	Microsoft Dataverse Remote Code Execution Vulnerability	8.7 HIGH AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N	Remote Code Execution (Deserialization)	RCE in Microsoft Dataverse (cloud service) due to deserialization of untrusted data.	RCE within Dataverse environment; S:C implies impact beyond initial component, affecting connected cloud resources. Data compromise/manipulation.
CVE-2025-33072	Microsoft msagsfeedback.azurewebsites.net Information Disclosure Vulnerability	8.1 HIGH AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N	Information Disclosure (Improper Access Control)	Improper access control in Azure (msagsfeedback.azurewebsites.net) allows information disclosure over network.	Unauthorized disclosure of sensitive information; high impact on Confidentiality and Integrity.
CVE-2025-29966	Remote Desktop Client Remote Code Execution Vulnerability	8.8 HIGH AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	Remote Code Execution (Heap-based Buffer Overflow)	Heap-based buffer overflow in Windows Remote Desktop allows RCE over network.	RCE on client machine with user’s privileges when connecting to malicious RDP server.

1. CVE-2025-29967 – Remote Desktop Client RCE: When Connecting Out is Dangerous

• 1. The Nitty-Gritty:
  CVE-2025-29967 is a critical RCE in the Windows Remote Desktop Client (RDC), caused by a heap-based buffer overflow. An attacker sets up a malicious RDP server. If your user connects to it, boom – code execution on their machine. It’s an 8.8 (High) CVSS, needs user interaction (the connection), and RDP clients are everywhere.
• 2. How Attackers Use It (MITRE ATT&CK Style):
  This is Execution (TA0002), potentially Initial Access (TA0001), via Exploitation for Client Execution (T1203). The weakness is Heap-based Buffer Overflow (CWE-122) – writing too much data to a memory bucket on the heap.
• 3. The Real-World Risk:
  Social engineering is key here: trick a user into RDPing to an attacker’s server. When the client tries to connect, the overflow happens, and the attacker’s code runs on the client with that user’s rights.
• 4. The Domino Effect (Attack Chain):
  This is a way in. If the user is standard, the attacker then looks for an EoP. The compromised client becomes a beachhead inside your network. Critical RCEs in common clients like RDP are prime targets for exploit development.
• 5. Your Defense Playbook:

• Patch It: May 2025 updates.
• Beyond Patching:

• User Training: “Only connect to RDP servers you know and trust!”
• Egress Filtering: Block outbound RDP (TCP/UDP 3389) from workstations unless absolutely necessary and to approved destinations only.

• Endpoint Monitoring: Watch mstsc.exe (RDP client) for connections to weird, external IPs. Look for suspicious child processes after an RDP session.

This is a “reverse RDP” attack. We spend so much time securing RDP servers (like against BlueKeep), but this shows the client can be the target. It flips the usual RDP threat model. Egress filtering and user awareness are vital.

1. CVE-2025-30377 & CVE-2025-30386 – Microsoft Office RCEs: The Perennial Threat

• 1. The Nitty-Gritty:
  May brings us more critical RCEs in Microsoft Office.

• CVE-2025-30377: Critical Office RCE. Details are a bit sparse in the initial snippets.
• CVE-2025-30386: A Use-After-Free in Office, also a critical RCE, CVSS 8.4 (High). Interestingly, NVD says “User Interaction: Not Required,” which is odd for Office RCEs that usually need a malicious file opened. This could mean a different, more direct local attack vector, or just an NVD quirk. Office is on virtually every corporate (and personal) machine, making these widespread threats.

• 2. How Attackers Use It (MITRE ATT&CK Style):
  Typically Execution (TA0002) or Initial Access (TA0001), via Exploitation for Client Execution (T1203). If it’s an email attachment, it’s Phishing: Spearphishing Attachment (T1566.002). For CVE-2025-30386, the weakness is Use After Free (CWE-416).
• 3. The Real-World Risk:
  The classic Office attack: attacker crafts a malicious Word, Excel, or PowerPoint file. They email it to a victim. Victim opens it. Attacker’s code runs with the victim’s privileges. If that UI:N for CVE-2025-30386 is real, it could be even nastier, perhaps triggered programmatically.
• 4. The Domino Effect (Attack Chain):
  Office RCEs are a go-to for initial access. Once in, attackers deploy more malware, steal creds, or use an EoP (like the ones also patched this month) for full control. Then it’s ransomware, data theft, you name it. Everyone from script kiddies to nation-states uses Office exploits.
• 5. Your Defense Playbook:

• Patch It: May 2025 Office updates.
• Beyond Patching:

• Email/Web Security Gateways: Scan attachments and downloads for malicious Office files.
• User Training: “Don’t open weird Office files! Don’t enable macros from untrusted sources!”
• Office Attack Surface Reduction (ASR) Rules: Configure these to block common Office attack techniques (like Office apps spawning child processes).
• Protected View: Make sure it’s on for docs from the internet.
• EDR: Monitor Office apps for weird behavior (spawning shells, unusual network connections, dropping executables).

• Endpoint Monitoring: Watch Office app processes (winword.exe, excel.exe, etc.) for suspicious child processes or file creation.

Office docs are still a super popular way to deliver malware. They’re everywhere, file formats are complex (lots of places for bugs to hide), and users are used to opening them. The constant stream of critical Office RCEs shows this is an ongoing battle.

1. CVE-2025-47732 – Microsoft Dataverse RCE: Trouble in Low-Code Paradise

• 1. The Nitty-Gritty:
  CVE-2025-47732 is a critical RCE in Microsoft Dataverse, a cloud-based data service that’s the backbone for many Dynamics 365 and Power Platform apps. Microsoft calls this “exclusively-hosted-service,” meaning they patch the service itself. The bug is due to Deserialization of Untrusted Data, with a CVSS of 8.7 (High). It needs low privileges (PR:L), user interaction (UI:R), and critically, Scope: Changed (S:C) – meaning an exploit can break out beyond just Dataverse. This is a big deal for orgs deep in Microsoft’s business app ecosystem.
• 2. How Attackers Use It (MITRE ATT&CK Style):
  In a cloud context, this is Execution (TA0002) or Initial Access (TA0001). The weakness is Deserialization of Untrusted Data (CWE-502) – the app trusts serialized data too much, and attackers can craft malicious objects that execute code when deserialized. The “Scope: Changed” is a major red flag.
• 3. The Real-World Risk:
  An attacker with low-level access in Dataverse (e.g., a limited user in a Power App) crafts a malicious request. The victim interacts in a way that processes this bad data (e.g., using a compromised Power App, a dodgy data import). The deserialization flaw triggers RCE in the Dataverse service. “Scope: Changed” means the attacker might get access beyond just the vulnerable Dataverse bit, potentially hitting other connected cloud apps or data.
• 4. The Domino Effect (Attack Chain):
  RCE in Dataverse could be catastrophic: steal/modify sensitive business data (customer records, financials), mess with business logic in apps, disrupt critical processes, or use Dataverse as a launchpad into the wider cloud environment. No active exploitation mentioned yet.
• 5. Your Defense Playbook:

• Patches (Microsoft’s Job): Since it’s a hosted service, Microsoft patches Dataverse itself. Keep an eye on their advisories.
• Your Responsibilities (Customer-Side):

• Secure App Dev: For your custom Power Apps or Dynamics 365 bits that use Dataverse, validate all inputs and outputs rigorously.
• Least Privilege (Cloud Edition): Lock down user and app permissions for Dataverse.
• Audit Log Monitoring: Regularly check Dataverse, Power Platform, and Dynamics 365 logs for weird access or data manipulation.
• Vet Third-Party Stuff: Scrutinize any third-party solutions or custom connectors that touch Dataverse.

Bugs in core cloud services like Dataverse are scary. These platforms power tons of low-code/no-code apps and critical business systems, often built by “citizen developers” who aren’t security gurus. A flaw like this RCE (especially a CWE-502 with Scope: Changed) can have massive ripple effects. It’s a reminder that even in the cloud, security is a shared responsibility.

VII. The Clock is Ticking: Real-World Impact & Your Strategic Moves

1. Zero-Days in the Wild & The Patching Rat Race:

Five zero-days (CVE-2025-30400, CVE-2025-32701, CVE-2025-32706, CVE-2025-32709, CVE-2025-30397) are confirmed as actively exploited. That means the bad guys are already using them. Microsoft isn’t giving us much detail on how these are being used or any IoCs, which makes our jobs harder. We can’t easily hunt for these specific attacks, so patching fast and using behavioral detection are key.

Patching is always a challenge. This month alone, Microsoft dropped 72 fixes, not to mention all the third-party updates. IT teams are swamped. Limited time, staff, and budget, plus compatibility testing headaches and the fear of breaking something important – it all leads to delays. And with over 40,000 CVEs published in 2024 (a 38% jump from 2023!), the pressure is only mounting. This “patch management squeeze” – trying to keep up with a flood of vulnerabilities while attackers exploit them faster than ever – often means patches get delayed, and that’s exactly the window attackers jump through.

1. High-Profile Hits? (Too Soon to Tell, But History Bites):

It’s early days to link these specific May 2025 CVEs to big, named breaches. But history tells a story. CLFS driver zero-days? Ransomware gangs like RansomEXX and threat groups like Storm-2460 (with their PipeMagic malware) have loved those in the past. It’s a safe bet that these new, actively exploited bugs, especially the EoP ones, will quickly find their way into attacker toolkits for ransomware, data theft, and setting up persistent access.

1. Your Game Plan: Practical, Real-World Advice

1. Prioritize Like a Pro:

• NOW: The five actively exploited zero-days.
• NEXT: The two publicly disclosed zero-days.
• THEN: All other “Critical” bugs, especially RCEs. Use CVSS scores, vendor exploitability info, and your own risk assessment to guide this.

1. Assume Breach & Fortify Internally: With attackers getting SYSTEM access via EoP bugs, you have to assume they can get in. Beef up internal defenses:

• Network segmentation (limit lateral movement).
• Advanced EDR/XDR (behavioral detection for post-compromise).
• Strict least privilege (users and service accounts).
• Monitor for credential dumping (LSASS access) and lateral movement (PsExec, WMI abuse).

1. Speed Up Your Patching Cycle: Streamline your patch process. Automate where you can (especially for less critical systems). Have emergency patching procedures ready for actively exploited stuff.
2. Hunt Proactively (No IoCs? No Problem!): Since Microsoft isn’t giving specific IoCs for these zero-days, focus on TTP-based detection. Monitor the affected Windows components (CLFS, DWM, AFD). Watch for weird script execution (especially for CVE-2025-30397 via IE Mode). Hunt for common post-RCE/EoP techniques.
3. Train Your Humans (Again!): User education is vital, especially for bugs like CVE-2025-30397 (Scripting Engine RCE) and Office RCEs that need a user click. Phishing, dodgy attachments/links, risks of enabling macros – drill it into them.
4. Tackle Legacy Tech Head-On: Have a plan for old systems. Upgrade, isolate, or use compensating controls (virtual patching, intense monitoring). Get rid of IE Mode if you can, or lock it down tight with Enterprise Mode Site Lists.
5. Cloud Security is a Partnership: If you’re using Azure or Dataverse, stay on top of Microsoft’s patching. But remember the shared responsibility model. You are responsible for secure configs, identity management, and monitoring your cloud logs.

The lack of specific IoCs from Microsoft for these zero-days is a real pain. It forces us to rely on generic detection, vendor signatures (which can lag), and educated guesses from past attacks. This just hammers home the need for solid security fundamentals, good EDR/XDR with behavioral smarts, and a wide range of threat intel sources.

VIII. The Bottom Line: Stay Sharp, Patch Fast

1. The Nastiest Threats Recapped:

Microsoft’s May 2025 Patch Tuesday is a big one. Five actively exploited zero-days are the main event (CVE-2025-30400, CVE-2025-32701, CVE-2025-32706, CVE-2025-32709, CVE-2025-30397). Four of these give attackers SYSTEM-level EoP, one is an RCE via legacy browser tech. Two more zero-days were publicly known before fixes (CVE-2025-26685, CVE-2025-32702). Add in six “Critical” bugs (mostly RCEs) hitting Office, RDP, Azure, and Dataverse. Attackers are clearly focused on getting in (RCE) and then taking over (EoP).

1. Your Final Action Plan:

1. Patch Now, Patch Smart: Actively exploited zero-days first. Then publicly disclosed. Then Criticals. Risk-based prioritization is your friend.
2. Defense-in-Depth is Non-Negotiable: Assume breaches happen. Strengthen internal controls: microsegmentation, least privilege, EDR/XDR for behavior, monitor for lateral movement.
3. Hunt for TTPs: No IoCs for the zero-days? Hunt for known attacker techniques related to the affected components and general post-exploitation moves.
4. Deal With Legacy Debt: Have a plan for old systems and tech like IE Mode. Upgrade, isolate, or mitigate.
5. Users are Part of the Solution: Train them on phishing, bad links, and risky document habits.
6. Cloud Security is YOUR Responsibility Too: Understand the shared model. Secure your configs, manage identities, and watch those logs.

This Patch Tuesday is a clear signal: the threat landscape is fast, aggressive, and hitting critical system components. Proactive, agile, and deeply layered security isn’t just a nice-to-have – it’s essential for survival.

References

• [User Query] (Source of the initial request and context)
• 1 https://www.bleepingcomputer.com/news/microsoft/microsoft-may-2025-patch-tuesday-fixes-5-exploited-zero-days-72-flaws/
• 2 https://www.securityweek.com/zero-day-attacks-highlight-another-busy-microsoft-patch-tuesday/
• 3 https://www.action1.com/patch-tuesday/
• 4 https://www.zerodayinitiative.com/blog/2025/4/8/the-april-2025-security-update-review (Note: While dated April, content discussing EoP chaining is generally relevant)
• 5 https://sbscyber.com/blog/security-patch-overload
• 6 https://www.ninjaone.com/blog/risks-of-delayed-patching/
• 7 https://www.e-spincorp.com/patch-management-policies-the-strategic-foundation-of-organizational-security/
• 8 https://nvd.nist.gov/vuln/detail/CVE-2025-30400
• 9 https://feedly.com/cve/security-advisories/microsoft/2025-05-13-may-2025-patch-tuesday-10-critical-vulnerabilities-amid-78-cves
• 10 https://nvd.nist.gov/vuln/detail/CVE-2025-32701
• 11 https://nvd.nist.gov/vuln/detail/CVE-2025-32706
• 12 https://nvd.nist.gov/vuln/detail/CVE-2025-32709
• 13 https://nvd.nist.gov/vuln/detail/CVE-2025-30397
• 14 https://www.cve.org/CVERecord?id=CVE-2025-24073 (Note: This CVE is for DWM Core Library but cited as an example of affected products, the primary CVE for DWM in this report is CVE-2025-30400)
• 15 https://cwe.mitre.org/data/definitions/416.html
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• 24 https://securityboulevard.com/2024/10/kev-cwe-attack-vector-%E2%9D%A4%EF%B8%8F%F0%9F%94%A5/
• 25 https://advisories.checkpoint.com/defense/advisories/public/2025/cpai-2025-0292.html
• 26 https://nvd.nist.gov/vuln/detail/CVE-2025-26685
• 27 https://nvd.nist.gov/vuln/detail/CVE-2025-32702
• 28 https://cwe.mitre.org/data/definitions/287.html
• 29 https://www.armis.com/blog/deepseek-and-the-security-risks-part-ii-when-automation-goes-wrong/
• 30 https://www.incibe.es/en/incibe-cert/blog/tacticas-y-tecnicas-los-malos-sci
• 31 https://cwe.mitre.org/data/definitions/77.html
• 32 https://www.cisa.gov/news-events/cybersecurity-advisories/aa25-022a
• 33 https://sparta.aerospace.org/v2.0/technique/IMP-0004 (General CWE listing including CWE-77)
• 34 https://nvd.nist.gov/vuln/detail/CVE-2025-29967
• 35 https://www.reddit.com/r/sysadmin/comments/1klcpkl/patch_tuesday_megathread_20250513/ (User Automox_ comment)
• 36 https://nvd.nist.gov/vuln/detail/CVE-2025-30386
• 37 https://nvd.nist.gov/vuln/detail/CVE-2025-47732
• 38 https://nvd.nist.gov/vuln/detail/CVE-2025-33072
• 39 https://www.cvedetails.com/cve/CVE-2025-33072/
• 40 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-33072
• 41 https://nvd.nist.gov/vuln/detail/CVE-2025-29966
• 42 https://cwe.mitre.org/data/definitions/122.html
• 43 https://github.com/YoussefJeridi/vulTensorflow (General CWE-122 description)
• 44 https://www.balbix.com/blog/patch-tuesday-update-april-2025/ (Discusses Office RCEs generally)
• 45 https://cwe.mitre.org/data/definitions/502.html
• 46 https://emb3d.mitre.org/threats/TID-326.html
• 47 https://docs.datadoghq.com/security/code_security/static_analysis/static_analysis_rules/python-security/yaml-load/
• 48 https://www.pixelstech.net/article/1720938411-iot-system-cyber-attack-case-study-02%3A-python-deserialization-attack-and-library-hijacking-attack
• 49 https://preyproject.com/blog/the-future-of-cybersecurity-in-schools-trends-tips-and-tools
• 50 https://www.neuroquantology.com/open-access/CLOUD+SECURITY+CHALLENGES+IN+EDUCATION%253A+RISKS+AND+SOLUTIONS_14568/?download=true
• 51 https://edtechmagazine.com/k12/article/2025/03/3-cloud-vulnerabilities-schools-need-watch-for-perfcon
• 52 https://blog.blackbaud.com/top-cyber-threats-to-educational-institutions/
• 53 https://www.paubox.com/blog/how-legacy-systems-disrupt-patient-care
• 54 https://www.certinal.com/blog/legacy-systems-in-healthcare-slowing-growth
• 55 https://www.redactable.com/blog/healthcare-data-breaches-consequences-and-how-to-prevent-them
• 56 https://microtime.com/healthcare-data-breaches-rising-threats-costs-in-2025/
• 57 https://www.bleepingcomputer.com/news/microsoft/microsoft-april-2025-patch-tuesday-fixes-exploited-zero-day-134-flaws/ (Context on RansomEXX and CLFS)
• 3 https://isc.sans.edu/diary/rss/31946 (SANS ISC Summary for May 2025)

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Continuing Professional Education (CPE) Credit

Earn CPE credits for reading this Security Blotter article. This piece provides practical and technical insight into zero-day vulnerabilities, privilege escalation, and remote code execution threats targeting core Windows components. It is suitable for professionals maintaining credentials in cybersecurity, risk management, and incident response.

Article Overview

This article provides an in-depth analysis of Microsoft’s May 2025 Patch Tuesday, including the exploitation of five zero-day vulnerabilities, attacker tradecraft, detection strategies, sector-specific mitigation guidance, and prioritization tactics. The content aligns with core topics across security operations, incident response, governance, and software security domains.

• Word Count: 8,143

• URL: https://securityblotter.com/may-2025-patch-tuesday/

• Estimated Read Time: 41 minutes

• CPE Total: 0.75 CPE credits

• Publisher: Security Blotter

• Author: Jonathan Brennan – ISC2 Member ID 555001

🧾 CPE Submission Details

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