Microsoft Windows User Profile Service Privilege Escalation Vulnerability
CVE-2022-21919 is a security vulnerability in Microsoft Windows, added to CISA KEV on April 25, 2022. Patch order: third of four.
What it is
Microsoft Windows User Profile Service contains an unspecified vulnerability that allows for privilege escalation.
Who's affected
Affects anyone running Windows workstations or servers. In a small CPA, legal, or dental practice, Windows is typically the platform your accounting, document management, or practice management software runs on — exploitation gives an attacker access to whatever client files and credentials live on those machines.
What to do
Apply updates per vendor instructions.
If you don't have someone in-house to verify the patch deployed across every endpoint — or you're not sure whether you're affected — that's exactly the kind of triage we do. Book a free 20-minute triage call.
Insurance readiness
Your insurer will ask if this is patched.
Unpatched entries on CISA's Known Exploited Vulnerabilities list are exactly what cyber-insurance carrier questionnaires probe for, and knowing which controls they check is how you keep a renewal from stalling.
Get the free carrier questionnaire →Severity
CVSS base score: 7.0 — HIGH
Weakness classification: CWE-59
Microsoft fix
- KB5009557 (Security Update)
- KB5009545 (Security Update)
- KB5009543 (Security Update)
- KB5009555 (Security Update)
- KB5009566 (Security Update)
- KB5009585 (Security Update)
- KB5009546 (Security Update)
- KB5009610 (Monthly Rollup)
- KB5009621 (Security Only)
- KB5009624 (Monthly Rollup)
- KB5009595 (Security Only)
- KB5009627 (Monthly Rollup)
- KB5009601 (Security Only)
- KB5009586 (Monthly Rollup)
- KB5009619 (Security Only)
Microsoft Exploitability Index (assessed at update release): Exploitation More Likely
This CVE is on CISA's Known Exploited Vulnerabilities catalog. Microsoft's index reflects their release-time forecast, not current observed activity, and is not automatically revised upward when exploitation appears later.
Vendor workaround
No vendor workaround published. Patching is the only fix.
CISA due date
CISA's listed due date: May 16, 2022.
Federal civilian agencies work under CISA's Binding Operational Directive 26-04, which replaced BOD 22-01 on June 10, 2026. It sets the deadline for each affected system by:
- How exposed that system is to the internet
- Whether the attack can be automated
- How much control it gives an attacker
Its table gives catalogued vulnerabilities 3 or 14 days.
None of this binds a private business, but treat the date as a strong recommendation, especially if you handle regulated data (HIPAA, GLBA, ABA model rules).
EPSS
EPSS score: 2.4% — higher than 84% of all scored CVEs.
EPSS estimates the probability of exploitation activity in the next 30 days. Every entry on this site is already confirmed exploited, so read it as relative urgency among the things you still have open, not as permission to wait.
Other exploited Microsoft Windows entries
More CISA KEV entries for Microsoft Windows. Same product line, same actively-exploited status.
Source
This entry comes from CISA's Known Exploited Vulnerabilities catalog, public US-Government data we pull daily. The plain-language framing and the what-to-do guidance above are ours. View the original entry on cisa.gov.