May 2025 Patch Tuesday: Microsoft Preps Fixes for Broken Logins, Missed Patches, and Security Chaos

Written By Noel Bradford

Another month, another round of digital duct tape.

Microsoft's May 2025 Patch Tuesday will land like a fire extinguisher in a burning server room. After last month’s flood of 171 fixes and at least one nasty zero-day, this month looks quieter — but no less essential especially if you're still staring at broken Kerberos logins or wondering why your Windows Hello PIN is on strike.

What We’re Expecting

1. Kerberos Nightmare Continues (CVE-2025-26647)

Microsoft's April patch blitz did more than plug holes. It created a few of its own. Admins running domain controllers saw Kerberos authentication crumble like a biscuit in tea. With a known issue logged and temporary workarounds deployed, May should bring the long-promised fix. Relief is hopefully on the horizon for anyone who hasn't rolled back April's disaster.

2. Hello? Hello? Anyone?

Another April casualty: Windows Hello. On machines with Secure Launch and DRTM enabled, login using facial recognition or PIN went out the window. Microsoft has acknowledged the bug and suggested a full re-enrolment, which is not ideal. We expect a proper fix in the May batch.

3. The Mystery of the Vanishing Logs and Unpatched Holes

April fixed plenty of RCEs and privilege escalations, like CVE-2025-27480 (RDP Gateway RCE) and CVE-2025-27727 (Windows Installer elevation). However, several patches only landed for Windows 11. Windows 10, the forgotten child, still hasn’t seen those fixes. May should round things off. We’ll be watching those changelogs closely.

4. WSUS Is Having a Moment

April’s update also tripped up Windows 11 24H2 deployments via WSUS, throwing 0x80240069 errors like confetti. Microsoft issued a Known Issue Rollback (KIR) but has promised a formal fix with this month's updates. Fingers crossed it sticks.

5. The Quiet Ones: Stack Updates and Cumulative Grit

Beyond headline bugs, expect cumulative updates across all supported builds. These will mop up smaller CVEs, improve service stack reliability, and keep the OS behaving.

Anything Else from Redmond?

Expect at least one zero-day to be squashed (it wouldn’t be Patch Tuesday without it) and a grab-bag of fixes across core Windows components. Defender, SmartScreen, the Print Spooler (yes, still), and core system DLLs are all usual suspects. If you've got legacy systems, check for out-of-band fixes or delayed patches.

Adobe, Intel, SAP: Side Quests

While Microsoft is the headliner, don’t sleep on the others:

  • Adobe: Often releases security updates on the same day. Acrobat/Reader is overdue.

  • Intel: No major CPU CVEs flagged for May, but microcode updates could land.

  • SAP: Their April security note drop was heavy, with more expected mid-May. Check NetWeaver and S/4HANA installations.

Bottom Line

If April’s Patch Tuesday felt like a storm, May is the clean-up. Expect fixes for broken authentication, missing Windows 10 patches, and core OS bugs. It’s not glamorous, but it’s necessary. Especially if you enjoy logging in without swearing.

Watch for the update rollout on Tuesday, 14 May. As always, test before you patch. Or don’t, and enjoy the thrill.

Noel Bradford

Noel Bradford – Head of Technology at Equate Group, Professional Bullshit Detector, and Full-Time IT Cynic

As Head of Technology at Equate Group, my job description is technically “keeping the lights on,” but in reality, it’s more like “stopping people from setting their own house on fire.” With over 40 years in tech, I’ve seen every IT horror story imaginable—most of them self-inflicted by people who think cybersecurity is just installing antivirus and praying to Saint Norton.

I specialise in cybersecurity for UK businesses, which usually means explaining the difference between ‘MFA’ and ‘WTF’ to directors who still write their passwords on Post-it notes. On Tuesdays, I also help further education colleges navigate Cyber Essentials certification, a process so unnecessarily painful it makes root canal surgery look fun.

My natural habitat? Server rooms held together with zip ties and misplaced optimism, where every cable run is a “temporary fix” from 2012. My mortal enemies? Unmanaged switches, backups that only exist in someone’s imagination, and users who think clicking “Enable Macros” is just fine because it makes the spreadsheet work.

I’m blunt, sarcastic, and genuinely allergic to bullshit. If you want gentle hand-holding and reassuring corporate waffle, you’re in the wrong place. If you want someone who’ll fix your IT, tell you exactly why it broke, and throw in some unsolicited life advice, I’m your man.

Technology isn’t hard. People make it hard. And they make me drink.

https://noelbradford.com
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