CVE-2023-29336: Microsoft Win32K Privilege Escalation Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 9 May 2023, the same day the CVE record was published.

How likely is exploitation in the next 30 days?

41.2%

EPSS score, percentile 98.7 of all scored records

How severe?

7.8 High

CVSS v3.1 base score, given by the CNA

What should I do?

CISA deadline 30 May 2023. Apply updates per vendor instructions.

Advisories and patches (1)

Which versions are affected?

Affected

• from 10.0.10240.0 to before 10.0.10240.19926
• from 10.0.14393.0 to before 10.0.14393.5921
• from 10.0.14393.0 to before 10.0.14393.5921
• from 10.0.14393.0 to before 10.0.14393.5921
• from 6.0.6003.0 to before 6.0.6003.22070
• from 6.0.6003.0 to before 6.0.6003.22070

and 7 more in the table below

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 30 May 2023.

Advisories and patches

• Win32k Elevation of Privilege Vulnerability (Vendor advisory)

Linked from CISA's catalog entry

• https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2023-29336
• https://nvd.nist.gov/vuln/detail/CVE-2023-29336

Affected products and versions

As listed in the CVE record.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

Microsoft Win32k contains an unspecified vulnerability that allows for privilege escalation up to SYSTEM privileges.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2023-29336 to its Known Exploited Vulnerabilities (KEV) catalog on 9 May 2023.
• CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
• The due date CISA sets for the required action is 30 May 2023.
• The CVE record was published on 9 May 2023, the same day it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 7.8 (High), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 41.2% (percentile 98.7), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

Win32k Elevation of Privilege Vulnerability

Win32k Elevation of Privilege Vulnerability

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-416: Use After Free

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

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