Vulnerability in Linux

[ Description ]Official description

In the Linux kernel, the following vulnerability has been resolved: btrfs: take commit root semaphore when iterating in mark_block_group_to_copy() mark_block_group_to_copy() iterates over the commit root with skip_locking=true. A concurrent transaction commit can swap and free the commit root during iteration, causing use-after-free when accessing extent buffers. Fix it by using path->need_commit_sem to protect the commit root search.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund5 Oct 2026WID-SEC-2026-3743

  Linux Kernel: Multiple vulnerabilities Translated from German

  Risk mediumCVE-2026-98221CVE-2026-98181CVE-2026-98248+204 more CVEs

[ References ]References

• git.kernel.org/stable/c/0594e3423f4ba3137c734371169491f9a98e9af4
• git.kernel.org/stable/c/709f6a5e986535005110c6c69b322f63631cb200
• git.kernel.org/stable/c/8e2007b263ea250251ec3021a0a197da990ee1a8
• git.kernel.org/stable/c/93a025166495c63ba5b8ac721c7040d5312e8335
• git.kernel.org/stable/c/c32490c6d3f3a9f2d177d57c7eb8bbc347561d08