CVE-2026-50406Important

Windows Backup Engine Elevation of Privilege Vulnerability

Assessment

Use after free in Windows Backup Engine allows an authorized attacker to elevate privileges locally.

Severity: Important
CVSS base score: 7.0CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Impact: Elevation of Privilege
EPSS, next 30 days: 0.3%Higher than 18.2% of scored CVEs · FIRST model run 26 Sep 2026 · about EPSS
Exploitability: Exploitation Less Likely
Publicly disclosed: No
Customer action: Required: apply the update
Component: Windows Backup Engine
Weakness: CWE-416: Use After Free
Issued by: Microsoft
Published: 14 Jul 2026 · July 2026
Last revised: 14 Jul 2026

3 KBs

KB	Type	Restart	Applies to	Other CVEs
KB5099539	Security Update	Required	Windows 10 Version 21H2 for 32-bit Systems, Windows 10 Version 21H2 for ARM64-based Systems, Windows 10 Version 21H2 for x64-based Systems and 3 more	All CVEs in KB5099539
KB5101649	Security Update	Required	Windows 11 Version 26H1 for ARM64-based Systems, Windows 11 version 26H1 for x64-based Systems	All CVEs in KB5101649
KB5101650	Security Update	Required	Windows 11 Version 24H2 for ARM64-based Systems, Windows 11 Version 24H2 for x64-based Systems, Windows 11 Version 25H2 for ARM64-based Systems and 1 more	All CVEs in KB5101650

ESU, Windows

12 affected products