Microsoft Windows Common Log File System (CLFS) Driver Privilege Escalation Vulnerability
CVE-2022-37969 is a security vulnerability in Microsoft Windows, added to CISA KEV on September 14, 2022. Patch priority: Plan to patch.
What it is
Microsoft Windows Common Log File System (CLFS) driver contains an unspecified vulnerability that allows for privilege escalation.
VulnCheck tracked exploitation 1 day before CISA's KEV listing. VulnCheck's broader catalog of in-the-wild exploitation evidence picked this up before it landed on CISA's formal list. Per-CVE fact about this entry; not a population claim about lead time in general.
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: 7.8 — HIGH
Weakness classification: CWE-787
Microsoft fix
- KB5017315 (Security Update)
- KB5017308 (Security Update)
- KB5017316 (Security Update)
- KB5017392 (Security Hotpatch Update)
- KB5017328 (Security Update)
- KB5017327 (Security Update)
- KB5017305 (Security Update)
- KB5017361 (Monthly Rollup)
- KB5017373 (Security Only)
- KB5017367 (Monthly Rollup)
- KB5017365 (Security Only)
- KB5017358 (Monthly Rollup)
- KB5017371 (Security Only)
- KB5017370 (Monthly Rollup)
- KB5017377 (Security Only)
Microsoft Exploitability Index (assessed at update release): Exploitation Detected
Microsoft has confirmed in-the-wild exploitation in the latest software release. This aligns with CISA's listing of this CVE.
Vendor workaround
No vendor workaround published. Patching is the only fix.
CISA due date
Federal deadline: October 5, 2022. Federal agencies must complete the required action by this date. For private SMBs the deadline is advisory — but treat it as a strong recommendation, especially if you handle regulated data (HIPAA, GLBA, ABA model rules).
EPSS
EPSS score: 28.3% — higher than 98% 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.