CVE-2026-31448: Linux kernel · ext4: avoid infinite loops caused by residual data
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.4 Critical · fixed in 3.13.0-215.266 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 42% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.13.0-215.266, 4.4.0-1157.163, 4.15.0-1205.220~14.04.1 +121
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 22 Apr 2026
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 25.10linuxpkg:deb/ubuntu/linux?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle?arch=source&distro=questingOther 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 fix is available and included in Linux kernel versions 6.8.0-1057.58 and later. Users should update their Linux kernel to these fixed versions or newer to resolve the vulnerability. After updating, a system reboot is required to apply the changes. Due to ABI changes, recompilation and reinstallation of third-party kernel modules may be necessary. No additional mitigations are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's ext4 file system was resolved that could cause infinite loops during directory creation or node creation operations. The issue arises when an error occurs inserting a new extent into the extent tree, leading to inconsistent metadata and a deadlock condition where the inode lock cannot be released. This results in prolonged blocking of tasks and potential metadata corruption. The flaw affects certain Linux kernel versions and has been fixed in later kernel releases.
References
- ubuntu.com/security/CVE-2026-31448 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-31448 (opens in a new tab)
- git.kernel.org/linus/5422fe71d26d42af6c454ca9527faaad4e677d6c (opens in a new tab)
- ubuntu.com/security/notices/USN-8490-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8491-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8497-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8498-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8499-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8508-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8490-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8492-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8545-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8546-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8604-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8605-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8606-1 (opens in a new tab)