CVE-2026-103577: high-severity vulnerability in Microsoft Windows 11 version 23H2
Microsoft QUIC Security Feature Bypass Vulnerability
Published
18Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5
exploitation probability
—
observed exploitation
nono source reports it
Insecure default variable initialization in Microsoft QUIC allows an unauthorized attacker to bypass a security feature over a network.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H/E:U/RL:O/RC:C
Affected products
Microsoft · Windows 11 version 23H2Microsoft · Windows 11 Version 24H2Microsoft · Windows 11 Version 25H2Microsoft · Windows 11 version 26H1Microsoft · Windows 11 Version 26H2Microsoft · Windows Server 2022Microsoft · Windows Server 2025Microsoft · Windows Server 2025 (Server Core installation)Related CVEs — Microsoft Windows 11 version 23H2
In the same product, most dangerous first.
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