CVE-2026-74318: Linux kernel · btrfs: fix deadlock cloning inline extent when using flushoncommit
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 7.0.0-1014.14~24.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 12:55 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-1014.14~24.04.1, 7.0.0-1017.17~24.04.1, 7.0.0-1016.16~24.04.1 +11
Exploitation evidence
Disclosed: evidence found.
CVE published 15 Aug 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 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther 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
An official patch is available and should be applied to affected Linux kernel versions to resolve the deadlock issue. Users should update to the fixed kernel versions as provided by their Linux distribution. No additional mitigation is indicated by the vendor advisory.
Description
A deadlock vulnerability in the Linux kernel's Btrfs filesystem was fixed related to cloning inline extents when using the flushoncommit mount option. The issue involved a deadlock occurring during reflink and transaction commit operations when copying inline extent data to a destination file at offsets greater than zero. This flaw could cause kernel tasks to block indefinitely. The vulnerability has been addressed by ensuring proper file size updates when copying inline extents. Multiple specific Linux kernel versions are affected, and a patch is available.
References
- nvd.nist.gov/vuln/detail/CVE-2026-74318 (opens in a new tab)
- git.kernel.org/stable/c/06283034cec0fa357cbd85784ef7d3f5b2ce0790 (opens in a new tab)
- git.kernel.org/stable/c/2aa37c8ef1092c6f088e23a90bffefc672831c09 (opens in a new tab)
- git.kernel.org/stable/c/532085d00eb54c074bdeae648b194765239f4d11 (opens in a new tab)
- git.kernel.org/stable/c/ea3452726ccb6bcaa732f43cc57bb928eca3dd59 (opens in a new tab)
- ubuntu.com/security/CVE-2026-74318 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-74318 (opens in a new tab)
- git.kernel.org/linus/532085d00eb54c074bdeae648b194765239f4d11 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-3 (opens in a new tab)