Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
CVE-2026-26177 is an elevation-of-privilege vulnerability in the Windows Ancillary Function Driver for WinSock (AFD). Microsoft describes the flaw as a use-after-free condition. A locally authorized attacker with low privileges can exploit the bug to elevate privileges on the target system. Exploitation requires winning a race condition, which increases attack complexity, but no user interaction is required. Microsoft rated the issue Important and assigned CVSS 3.1 7.0 (AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H).
Are you exposed to this one?
Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.
Impact, mitigation & remediation
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
Impact
What an attacker gets, and what they’ve been doing with it.
Mitigation
If you can’t patch tonight, do this now.
Remediation
Patch, then assume compromise.
Exploits
No public exploits tracked yet. Mallory keeps watching.
No public exploit code observed for this vulnerability.
Affected products & vendors
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
Recent activity
2 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A Windows Ancillary Function Driver for WinSock elevation of privilege vulnerability.
A local elevation of privilege vulnerability in the Windows Ancillary Function Driver for WinSock caused by a use-after-free condition. Successful exploitation can allow an authorized attacker to gain SYSTEM privileges, though exploitation is considered less likely due to high attack complexity and a required race condition.
The version that knows your environment.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.