Hazard

Is CVE-2021-36934 being exploited?

Weaponised and widely attempted

Reliable public exploit code exists, or mass exploitation attempts are probable. Patch inside days, not weeks.

Microsoft Windows SAM Local Privilege Escalation Vulnerability

Microsoft · Windows

CVSS 7.8 EPSS 67% no public exploit indexed Fix deadline passed 24 February 2022

What it is

If a Volume Shadow Copy (VSS) shadow copy of the system drive is available, users can read the SAM file which would allow any user to escalate privileges to SYSTEM level.

Why we say that

  • EPSS puts exploitation in the next 30 days at 67%
  • CISA's federal remediation deadline (2022-02-24) has passed
  • Listed in the CISA Known Exploited Vulnerabilities catalogue

Every line above comes from a named public source. Where the evidence is thin, we say so rather than inventing confidence — see methodology.

What to do

Apply updates per vendor instructions.

What it costs when this goes wrong

This is where UK enforcement meets the vulnerability record. Where an unfixed vulnerability leads to a breach, the ICO treats it as a security failure under UK GDPR. Recent cases:

All UK cases caused by unpatched software →