CVE-2024-56759: Linux kernel · Use After Free
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 30 Oct 2026, 00:55 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 6 Jan 2025
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
A fix for this vulnerability has been implemented in the Linux kernel by moving the tracepoint call to before the extent buffer is freed. Users should apply the official kernel updates that include this fix. Since this is a kernel-level issue, upgrading to a patched kernel version is the recommended mitigation. No additional workarounds or mitigations are indicated.
Description
CVE-2024-56759 is a high-severity use-after-free vulnerability in the Linux kernel's Btrfs filesystem. It occurs when a tree block is copy-on-written (COW) with tracing enabled and kernel preemption active, leading to a potential use-after-free condition in the extent buffer during tracepoint execution. The flaw arises because the last reference to the extent buffer may be dropped before the tracepoint is called, causing the buffer to be freed prematurely. The issue has been fixed by relocating the tracepoint call to ensure it occurs before the extent buffer is freed.
References
- nvd.nist.gov/vuln/detail/CVE-2024-56759 (opens in a new tab)
- git.kernel.org/stable/c/44f52bbe96dfdbe4aca3818a2534520082a07040 (opens in a new tab)
- git.kernel.org/stable/c/526ff5b27f090fb15040471f892cd2c9899ce314 (opens in a new tab)
- git.kernel.org/stable/c/66376f1a73cba57fd0af2631d7888605b738e499 (opens in a new tab)
- git.kernel.org/stable/c/9a466b8693b9add05de99af00c7bdff8259ecf19 (opens in a new tab)
- git.kernel.org/stable/c/ba5120a2fb5f23b4d39d302e181aa5d4e28a90d1 (opens in a new tab)
- git.kernel.org/stable/c/c3a403d8ce36f5a809a492581de5ad17843e4701 (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)