CVE-2026-27912

Published Apr 14, 2026

Last updated 5 months ago

Windows Kerberos

Windows

Overview

AI description

Automated description summarized from trusted sources.

CVE-2026-27912 is an improper authorization vulnerability found within Windows Kerberos. This flaw allows an authorized attacker to elevate their privileges when operating over an adjacent network. The vulnerability, classified under CWE-285 (Improper Authorization), stems from the Kerberos authentication protocol's failure to properly validate authorization controls. This enables attackers with initial network access to bypass authorization checks and gain elevated privileges within the affected Windows environment. This vulnerability is also referred to as "ResetNightmare".

Description: Improper authorization in Windows Kerberos allows an authorized attacker to elevate privileges over an adjacent network.
Source: secure@microsoft.com
NVD status: Analyzed
Products: windows_server_2012, windows_server_2016, windows_server_2019, windows_server_2022, windows_server_2022_23h2, windows_server_2025

Risk scores

CVSS 3.1

Type: Primary
Base score: 8
Impact score: 5.9
Exploitability score: 2.1
Vector string: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity: HIGH

Weaknesses

secure@microsoft.com: CWE-285

Hype score: Not currently trending

Configurations

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]

References

Sources include official advisories and independent security research.