Deadlock in Linux kernel - CVE-2026-90265
Published: September 18, 2026
Vulnerability identifier: #VU151209
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-90265
CWE-ID: CWE-833
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper lock ordering in btrfs defragmentation when reserving delayed-allocation space while holding dirty and locked folios and an extent-range lock. A local user can perform filesystem operations that trigger btrfs defragmentation to cause a denial of service.
The deadlock was observed with autodefrag and flushoncommit enabled.
Affected software
Linux kernel
How to mitigate CVE-2026-90265
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3