CVE-2021-4149: Debian Linux

Medium severity, CVSS 5.5. EPSS: 0.4% chance of exploitation in the next 30 days.

A vulnerability was found in btrfs_alloc_tree_b in fs/btrfs/extent-tree.c in the Linux kernel due to an improper lock operation in btrfs. In this flaw, a user with a local privilege may cause a denial of service (DOS) due to a deadlock problem.

Affected products

• Debian Debian Linux: version 9.0 only
• Linux Linux Kernel: before 5.15 (fixed in 5.15); version 5.15 only

Published 2022-03-23. Last modified 2026-06-17.