CVE-2023-29336: in the CISA KEV catalogue
Microsoft Win32K Privilege Escalation Vulnerability. CISA added CVE-2023-29336 to the Known Exploited Vulnerabilities catalogue on 2023-05-09 with a default due date of 2023-05-30. Known ransomware campaign use: Unknown. Forensic triage flag: No.
Microsoft Win32k contains an unspecified vulnerability that allows for privilege escalation up to SYSTEM privileges. (CISA description)
- Vendor / product
- Microsoft Win32k
- CWE
- CWE-416
- CISA required action
- Apply updates per vendor instructions.
- EPSS
- 41%, percentile 98 (scored 2026-11-03)
EPSS puts about 41 in 100 odds (41%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 98% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.
Vendor and reference links (from CISA)
Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.
Frequently asked questions
Is CVE-2023-29336 in the CISA KEV catalogue?
Yes. CISA added CVE-2023-29336 (Microsoft Win32K Privilege Escalation Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2023-05-09. CISA's default due date for it is 2023-05-30.
Is CVE-2023-29336 used in ransomware attacks?
CISA marks known ransomware campaign use as Unknown for CVE-2023-29336. That means CISA lacks confirmation, not that ransomware groups do not use it.
What should I do about CVE-2023-29336?
CISA's required action: Apply updates per vendor instructions.
Sources
- CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
- FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
- NVD record for CVE-2023-29336