CVE-2024-49868: Linux kernel · btrfs: fix a NULL pointer dereference when failed to start a new trasacntion
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.4.0-1142.152~18.04.1 : update Linux kernel when convenient.
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:N/I:N/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 should be applied. Fixed kernel versions include 5.4.0-1142.152~18.04.1, 5.4.0-1145.152~18.04.1, 5.4.0-1143.152~18.04.1, 5.4.0-208.228~18.04.1, 5.4.0-1086.91~18.04.1, 5.4.0-1138.147~18.04.1, 5.4.0-1129.142~18.04.1, 5.4.0-208.228, 5.4.0-1140.150, and 5.15.0-1073.79~20.04.1. Users should upgrade to these or later kernel versions to remediate the issue.
Description
CVE-2024-49868 is a vulnerability in the Linux kernel's Btrfs filesystem that causes a NULL pointer dereference when a new transaction fails to start. This occurs due to improper error handling in the transaction and relocation code paths, leading to a crash (general protection fault). The issue is fixed by adding a check to prevent dereferencing a NULL pointer during relocation root updates.
References
- ubuntu.com/security/CVE-2024-49868 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2024-49868 (opens in a new tab)
- git.kernel.org/linus/c3b47f49e83197e8dffd023ec568403bcdbb774b (opens in a new tab)
- git.kernel.org/stable/c/d73d48acf36f57362df7e4f9d76568168bf5e944 (opens in a new tab)
- git.kernel.org/stable/c/37fee9c220b92c3b7bf22b51c51dde5364e7590b (opens in a new tab)
- git.kernel.org/stable/c/d13249c0df7aab885acb149695f82c54c0822a70 (opens in a new tab)
- git.kernel.org/stable/c/7ad0c5868f2f0418619089513d95230c66cb7eb4 (opens in a new tab)
- git.kernel.org/stable/c/dc02c1440705e3451abd1c2c8114a5c1bb188e9f (opens in a new tab)
- git.kernel.org/stable/c/39356ec0e319ed07627b3a0f402d0608546509e6 (opens in a new tab)
- git.kernel.org/stable/c/c3b47f49e83197e8dffd023ec568403bcdbb774b (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)