CVE-2024-56581: Linux kernel · btrfs: ref-verify: fix use-after-free after invalid ref action
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 30 Oct 2026, 00:49 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 Dec 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
AI-suggested
The vulnerability has been resolved in the Linux kernel by fixing the code to remove the reference entry from the red-black tree before freeing it. Users and administrators should apply the official Linux kernel updates that include this fix.
Description
CVE-2024-56581 is a use-after-free vulnerability in the btrfs filesystem implementation of the Linux kernel. It occurs in the btrfs_ref_tree_mod() function when an invalid ref action leads to freeing a reference entry without properly removing it from the red-black tree, causing a use-after-free condition. This flaw has been fixed by ensuring the reference entry is removed from the tree before being freed.
References
- nvd.nist.gov/vuln/detail/CVE-2024-56581 (opens in a new tab)
- git.kernel.org/stable/c/4275ac2741941c9c7c2293619fdbacb9f70ba85b (opens in a new tab)
- git.kernel.org/stable/c/6370db28af9a8ae3bbdfe97f8a48f8f995e144cf (opens in a new tab)
- git.kernel.org/stable/c/6fd018aa168e472ce35be32296d109db6adb87ea (opens in a new tab)
- git.kernel.org/stable/c/7c4e39f9d2af4abaf82ca0e315d1fd340456620f (opens in a new tab)
- git.kernel.org/stable/c/a6f9e7a0bf1185c9070c0de03bb85eafb9abd650 (opens in a new tab)
- git.kernel.org/stable/c/d2b85ce0561fde894e28fa01bd5d32820d585006 (opens in a new tab)
- git.kernel.org/stable/c/dfb9fe7de61f34cc241ab3900bdde93341096e0e (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/03/msg00001.html (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/03/msg00002.html (opens in a new tab)