CVE-2026-20929

Windows HTTP.sys Elevation of Privilege Vulnerability

Improper access control in Windows HTTP.sys allows an authorized attacker to elevate privileges over a network.

Affected

Microsoft · Windows 10 Version 1607 · Windows 10 Version 1809 · Windows 10 Version 21H2 · Windows 10 Version 22H2 · Windows 11 version 23H2 · Windows 11 Version 23H2

CVSS v3.1 MICROSOFT

7.5 HIGHCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

2.87% chance of exploitation in the next 30 days, 87th percentile

Published

2026-01-13

Updated

2026-07-30

Proof-of-concept exploits (1)

• BenZamir/MITM6-Kerberos-CNAME-Abuse109★ · 2026-01-27

Metasploit modules (3)

• rapid7/metasploit-framework/blob/master/modules/auxiliary/server/relay/esc8_kerberos.rb
• rapid7/metasploit-framework/blob/master/modules/auxiliary/spoof/dhcp/dhcpv6_dns_takeover…
• rapid7/metasploit-framework/blob/master/modules/auxiliary/spoof/ipv6/ipv6_ra_dns_takeover…

Security advisories

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20929

References

• CVE Record
• NVD entry

Related

• CVE-2026-7791