CVE-2025-38626: Linux kernel · f2fs: fix to trigger foreground gc during f2fs_map_blocks() in lfs mode w/ "mode=lfs
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.15.0-1112.119~20.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1112.119~20.04.1, 5.15.0-1117.126~20.04.1, 5.15.0-1117.126~20.04.2 +65
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 22 Aug 2025
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.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | 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-aws-6.14pkg:deb/ubuntu/linux-aws-6.14?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– |
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 to affected Linux kernel versions. The vendor advisory from Ubuntu confirms that this issue has been fixed in updated kernel packages. Users should update their Linux kernel to a version that includes this fix to prevent system panics related to this vulnerability.
Description
A vulnerability in the Linux kernel's f2fs file system was fixed that could cause a system panic when using the 'mode=lfs' mount option. The issue occurs because foreground garbage collection (gc) was only triggered after block allocation, which could lead to out-of-space conditions and kernel BUGs during parallel writes. The fix allows foreground gc to trigger prior to block allocation in f2fs_map_blocks(). This vulnerability affects multiple Linux kernel versions and has a medium severity rating with a CVSS score of 5.5.
References
- ubuntu.com/security/CVE-2025-38626 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-38626 (opens in a new tab)
- git.kernel.org/linus/1005a3ca28e90c7a64fa43023f866b960a60f791 (opens in a new tab)
- git.kernel.org/stable/c/1005a3ca28e90c7a64fa43023f866b960a60f791 (opens in a new tab)
- git.kernel.org/stable/c/264ede8a52f18647ed5bb5f2bd9bf54f556ad8f5 (opens in a new tab)
- git.kernel.org/stable/c/385e64a0744584397b4b52b27c96703516f39968 (opens in a new tab)
- git.kernel.org/stable/c/82765ce5c7a56f9309ee45328e763610eaf11253 (opens in a new tab)
- git.kernel.org/stable/c/f289690f50a01c3e085d87853392d5b7436a4cee (opens in a new tab)
- ubuntu.com/security/notices/USN-7879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7879-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7880-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7879-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7879-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7934-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8031-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-5 (opens in a new tab)