CVE-2024-49867: Linux kernel · btrfs: wait for fixup workers before stopping cleaner kthread during umount
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.4.0-1142.152~18.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 23:43 UTC
- Patch
- Available – fixed in 5.4.0-1142.152~18.04.1, 5.4.0-1145.152~18.04.1, 5.4.0-1143.152~18.04.1 +80
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 21 Oct 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-7166-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7186-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7186-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7194-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7276-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7277-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7293-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7294-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7295-1 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-nvidiapkg:deb/ubuntu/linux-azure-nvidia?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and has been released in multiple Linux kernel versions including 5.4.0-1142.152 and later, as well as 5.15.0-1073.79 and later. Users and administrators should apply these kernel updates promptly to mitigate the vulnerability. No additional mitigation steps are required beyond applying the official fixes provided by the vendor.
Description
CVE-2024-49867 is a high-severity vulnerability in the Linux kernel's Btrfs file system. It occurs during unmount operations where the cleaner kernel thread is stopped without waiting for fixup worker threads to complete, leading to a use-after-free condition. This flaw can cause kernel crashes due to accessing freed memory structures. The issue has been fixed by ensuring that all fixup workers complete before stopping the cleaner thread. Multiple Linux kernel versions are affected, and patches have been released to address this vulnerability.
References
- ubuntu.com/security/CVE-2024-49867 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2024-49867 (opens in a new tab)
- git.kernel.org/linus/41fd1e94066a815a7ab0a7025359e9b40e4b3576 (opens in a new tab)
- git.kernel.org/stable/c/70b60c8d9b42763d6629e44f448aa5d8ae477d61 (opens in a new tab)
- git.kernel.org/stable/c/4c98fe0dfa2ae83c4631699695506d8941db4bfe (opens in a new tab)
- git.kernel.org/stable/c/9da40aea63f8769f28afb91aea0fac4cf6fbbb65 (opens in a new tab)
- git.kernel.org/stable/c/ed87190e9d9c80aad220fb6b0b03a84d22e2c95b (opens in a new tab)
- git.kernel.org/stable/c/bf0de0f9a0544c11f96f93206da04ab87dcea1f4 (opens in a new tab)
- git.kernel.org/stable/c/65d11eb276836d49003a8060cf31fa2284ad1047 (opens in a new tab)
- git.kernel.org/stable/c/41fd1e94066a815a7ab0a7025359e9b40e4b3576 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7186-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7186-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7194-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7166-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7276-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7277-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7293-1 (opens in a new tab)