How severe is CVE-2023-21768?

CVE-2023-21768 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-21768 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 65% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-21768?

CVE-2023-21768 primarily affects Microsoft Windows 11. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-21768?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-21768 published?

CVE-2023-21768 was published on 2023-01-10 and last updated on 2026-06-17.

CVE-2023-21768

CVE-2023-21768 is a high-severity vulnerability in Microsoft Windows 11 with a CVSS 3.x base score of 7.8. Its EPSS exploit-prediction score of 65% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-822.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 65% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-822
Affected product: Microsoft Windows 11
Published: 2023-01-10
Last modified: 2026-06-17

Description

Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability

Frequently asked questions

What is CVE-2023-21768?: Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
How severe is CVE-2023-21768?: CVE-2023-21768 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-21768 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 65% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-21768?: CVE-2023-21768 primarily affects Microsoft Windows 11. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-21768?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-21768 published?: CVE-2023-21768 was published on 2023-01-10 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21768

Affected products (5)

cpe:2.3:o:microsoft:windows_11:21h2:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_11:21h2:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_11:22h2:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_11:22h2:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2022:-:*:*:*:*:*:*:*

More vulnerabilities in Microsoft Windows 11

CVE-2022-34722 — Critical (CVSS 9.8): Windows Internet Key Exchange (IKE) Protocol Extensions Remote Code Execution Vulnerability
CVE-2022-34721 — Critical (CVSS 9.8): Windows Internet Key Exchange (IKE) Protocol Extensions Remote Code Execution Vulnerability
CVE-2022-34718 — Critical (CVSS 9.8): Windows TCP/IP Remote Code Execution Vulnerability
CVE-2022-30133 — Critical (CVSS 9.8): Windows Point-to-Point Protocol (PPP) Remote Code Execution Vulnerability
CVE-2022-29130 — Critical (CVSS 9.8): Windows Lightweight Directory Access Protocol (LDAP) Remote Code Execution Vulnerability
CVE-2022-22012 — Critical (CVSS 9.8): Windows Lightweight Directory Access Protocol (LDAP) Remote Code Execution Vulnerability

All CVEs affecting Microsoft Windows 11 →

Other CWE-822 vulnerabilities

CVE-2025-50165 — Critical (CVSS 9.8): Untrusted pointer dereference in Microsoft Graphics Component allows an unauthorized attacker to execute code over a…
CVE-2023-1437 — Critical (CVSS 9.8): All versions prior to 9.1.4 of Advantech WebAccess/SCADA are vulnerable to use of untrusted pointers. The RPC arguments…
CVE-2026-48137 — Critical (CVSS 9.1): There is an untrusted pointer dereference vulnerability in the NI grpc-device sideband streaming API that may allow an…
CVE-2025-4993 — Critical (CVSS 9.1): Untrusted Pointer Dereference vulnerability in RTI Connext Professional (Core Libraries) allows Pointer…
CVE-2025-1255 — Critical (CVSS 9.1): Untrusted Pointer Dereference vulnerability in RTI Connext Professional (Core Libraries) allows Pointer…
CVE-2024-36461 — Critical (CVSS 9.1): Within Zabbix, users have the ability to directly modify memory pointers in the JavaScript engine.

Browse all CWE-822 vulnerabilities →