Microsoft Win32k Privilege Escalation Vulnerability
A privilege escalation vulnerability exists when Windows improperly handles calls to Win32k.sys. An attacker who successfully exploited this vulnerability could run remote code in the security context of the local system.
- Vendor
- Microsoft
- Product
- Win32k
- CVSS
- 7.8
- EPSS (exploit probability)
- 3.0%
- Status
- kev
- CISA patch-by (BOD 22-01)
- Added to KEV
Is CVE-2018-8589 being exploited?
Yes. CISA added CVE-2018-8589 to its Known Exploited Vulnerabilities catalog on . CISA only lists a CVE when it has reliable evidence of exploitation in the wild.
FIRST's EPSS model puts the probability of exploitation activity in the next 30 days at 3.0% (scored October 14, 2026).
- CISA KEV[ LISTED ]
- ENISA EUVD (exploited)[ — ]
- CIRCL KEV[ — ]
Catalog snapshot 2026-11-13. Full cross-catalog view: /kev-comparison
CVE-2018-8589 timeline
Every event links to its source. Catalog dates are each catalog's own; day offsets count from NVD publication. Data: JSON
What to do
CISA required actionApply updates per vendor instructions.
US federal civilian agencies must remediate by (21 days after listing) under BOD 22-01. Everyone else: that deadline is a sensible upper bound, not a target. Vendor guidance and the NVD record are linked under Source above.
Other Microsoft Win32k CVEs we track
| CVE / Vulnerability | Severity | CVSS | EPSS | Added to KEV |
|---|---|---|---|---|
| CVE-2016-0165 Microsoft Win32k Privilege Escalation Vulnerability | [ HIGH ] | 7.8 | 13.7% | |
| CVE-2023-29336 Microsoft Win32K Privilege Escalation Vulnerability | [ HIGH ] | 7.8 | 41.2% | |
| CVE-2015-2360 Microsoft Win32k Privilege Escalation Vulnerability | [ HIGH ] | 8.8 | 14.8% | |
| CVE-2014-4113 Microsoft Win32k Privilege Escalation Vulnerability | [ HIGH ] | 7.8 | 86.6% | |
| CVE-2021-41357 Microsoft Win32k Privilege Escalation Vulnerability | [ HIGH ] | 7.8 | 1.5% | |
| CVE-2021-40450 Microsoft Win32k Privilege Escalation Vulnerability | [ HIGH ] | 7.8 | 1.5% | |
| CVE-2013-3660 Microsoft Win32k Privilege Escalation Vulnerability | [ HIGH ] | 7.8 | 39.3% | |
| CVE-2019-1132 Microsoft Win32k Privilege Escalation Vulnerability | [ HIGH ] | 7.8 | 9.9% |