CVE-2026-72437: Linux kernel · md/raid1: free r1_bio when REQ_NOWAIT is set and read would block on retry
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, 17:16 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% 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
A patch is available and should be applied to affected Linux kernel versions to resolve the memory leak issue. Users should update to the fixed kernel versions listed in the affectedVersions field. No additional mitigation actions are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's md/raid1 subsystem caused a memory leak of pre-allocated r1_bio structures when a read request with the REQ_NOWAIT flag was retried and the read would block. This issue has been resolved in specific Linux kernel versions. The leak occurs because the bio is completed and the function returns immediately without freeing the r1_bio, leading to resource leakage.
References
- nvd.nist.gov/vuln/detail/CVE-2026-72437 (opens in a new tab)
- git.kernel.org/stable/c/69ad6ce47f9bf2b9fe0ed69b042db993d33bbf12 (opens in a new tab)
- git.kernel.org/stable/c/6d92dbd73d19a0622f60352ce9d9379f7a760112 (opens in a new tab)
- git.kernel.org/stable/c/c66ed3e6371f5dba8f5d8ab810d6683ddc99201e (opens in a new tab)
- git.kernel.org/stable/c/c6e6354295845698d2fdfa20b71fc404786f7e93 (opens in a new tab)
- git.kernel.org/stable/c/d1eda529a4bf6b866d02755723ee0eb1f037a5ed (opens in a new tab)
- git.kernel.org/stable/c/db58075bc9c2ad2731f9c063859b47104bc2e7ef (opens in a new tab)
- ubuntu.com/security/CVE-2026-72437 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-72437 (opens in a new tab)
- git.kernel.org/linus/69ad6ce47f9bf2b9fe0ed69b042db993d33bbf12 (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)