Windows Server 2025
CVE-2026-20849
HIGH
Severity by source
AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Primary rating from Vendor (microsoft) · only source for this CVE.
CVSS VectorVendor: microsoft
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
2DescriptionCVE.org
Reliance on untrusted inputs in a security decision in Windows Kerberos allows an authorized attacker to elevate privileges over a network.
AnalysisAI
Windows Kerberos authentication in multiple Windows versions accepts untrusted input during security decisions, enabling authenticated network attackers to escalate privileges without user interaction. The vulnerability affects Windows 10 (versions 1607 and 1809), Windows Server 2012, and Windows Server 2025, with no patch currently available. An attacker with valid credentials can exploit this to gain elevated system access across the network.
Technical ContextAI
Affects Windows 10 1607. Reliance on untrusted inputs in a security decision in Windows Kerberos allows an authorized attacker to elevate privileges over a network.
RemediationAI
Monitor vendor advisories for a patch. Restrict network access to the affected service where possible.
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External POC / Exploit Code
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