CVE-2026-57093: Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Other sources
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17763.9020Patch KB5099538 - Upgrade
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Fixed in 10.0.28000.2525Patch KB5101649 - Upgrade
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Fixed in 10.0.26100.33158Patch KB5099536 - Upgrade
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Fixed in 10.0.26100.8875Patch KB5101650 - Upgrade
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Fixed in 10.0.19045.7548Patch KB5099539 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.19044.7548Patch KB5099539 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5386Patch KB5099540 - Upgrade
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Fixed in 6.3.9600.23291Patch KB5099444 - Upgrade
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Fixed in 10.0.14393.9339Patch KB5099535 - Upgrade
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Fixed in 6.2.9200.26226Patch KB5099445 - Upgrade
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Fixed in 10.0.26200.8875Patch KB5101650
Event History
Frequently Asked Questions
Who is realistically exposed to this issue?
Systems running the listed Microsoft Windows client or server products are in scope. Exploitation is local, so the primary exposure is on devices where an attacker can log on or otherwise execute code as an authorized low-privileged user.
What access does an attacker need to exploit it?
The attacker needs local access and low-level privileges; no user interaction is required. The supplied vector indicates that remote network-only exploitation is not the intended attack path.