CVE-2023-28229: Microsoft Windows CNG Key Isolation Service Privilege Escalation Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 4 Oct 2023, 176 days after the CVE record was published.

How likely is exploitation in the next 30 days?

1.7%

EPSS score, percentile 76.7 of all scored records

How severe?

7.0 High

CVSS v3.1 base score, given by the CNA

What should I do?

CISA deadline 25 Oct 2023. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Advisories and patches (1)

Which versions are affected?

Affected

• from 10.0.17763.0 to before 10.0.17763.4252
• from 10.0.0 to before 10.0.17763.4252
• from 10.0.17763.0 to before 10.0.17763.4252
• from 10.0.17763.0 to before 10.0.17763.4252
• from 10.0.20348.0 to before 10.0.20348.1668
• from 10.0.0 to before 10.0.19042.2846

and 14 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: 25 October 2023.

Advisories and patches

• Windows CNG Key Isolation Service Elevation of Privilege Vulnerability (Vendor advisory)

Linked from CISA's catalog entry

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-28229
• https://nvd.nist.gov/vuln/detail/CVE-2023-28229

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 Windows Cryptographic Next Generation (CNG) Key Isolation Service contains an unspecified vulnerability that allows an attacker to gain specific limited SYSTEM privileges.

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

• CISA added CVE-2023-28229 to its Known Exploited Vulnerabilities (KEV) catalog on 4 Oct 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 25 Oct 2023.
• The CVE record was published on 11 Apr 2023, 176 days before it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 7.0 (High), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 1.7% (percentile 76.7), 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

Windows CNG Key Isolation Service Elevation of Privilege Vulnerability

Windows CNG Key Isolation Service 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-591: Sensitive Data Storage in Improperly Locked Memory

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

Timeline

More exploited Microsoft vulnerabilities

• CVE-2026-96951: Microsoft Windows Command Injection Vulnerability (added 13 Oct 2026)
• CVE-2026-65660: Microsoft SharePoint Code Injection Vulnerability (added 25 Sep 2026)
• CVE-2026-81963: Microsoft Windows Link Following Vulnerability (added 8 Sep 2026)
• CVE-2026-85880: Microsoft Windows Heap-Based Buffer Overflow Vulnerability (added 8 Sep 2026)
• CVE-2019-1068: Microsoft SQL Server Remote Code Execution Vulnerability (added 26 Aug 2026)
• CVE-2026-33824: Microsoft Internet Key Exchange (IKE) Service Extensions Double Free Vulnerability (added 18 Aug 2026)