Executive brief
A security vulnerability exists in the Windows Backup Engine, a component responsible for managing system and file backups. An attacker who already has basic access to a computer could exploit this flaw to gain full administrative control over the system. This could allow them to access sensitive data, install malicious software, or disrupt business operations.
Technical details
A race condition (CWE-362) and potential use-after-free (CWE-416) vulnerability exists in the Windows Backup Engine due to improper synchronization during concurrent execution using shared resources. To exploit this, an attacker must first have local access to the target system with low-level user privileges. By successfully winning the race condition, the attacker can achieve elevated privileges, potentially reaching SYSTEM level. The vulnerability is tracked as CVE-2026-58598 and has been addressed in Microsoft's July 2026 security updates.
Affected products
- Microsoft Windows 10 Version 21H2 10.0.19044.0 to 10.0.19044.7548
- Microsoft Windows 10 Version 22H2 All versions affected
- Microsoft Windows 11 Version 24H2 10.0.26100.0 to 10.0.26100.8875
- Microsoft Windows 11 Version 25H2 10.0.26200.0 to 10.0.26100.8875
- Microsoft Windows 11 version 26H1 10.0.28000.0 to 10.0.28000.2525
Timeline
- 2026-07-16: disclosed
- 2026-07-16: advisory