CVE-2026-52930: Linux kernel · ipc/shm: serialize orphan cleanup with shm_nattch updates
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.15.0-1117.124~20.04.1 : 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 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +69
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 24 Jun 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 fix is available and has been incorporated in Linux kernel versions 5.15.0-1117.124~20.04.1 and later. Users and administrators should update to these fixed kernel versions or later to remediate this vulnerability. No additional mitigation actions are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's IPC shared memory subsystem was resolved by improving synchronization during orphaned segment cleanup. The issue involved improper serialization of updates to the shm_nattch field, potentially leading to incorrect decisions about segment removal. This flaw was fixed by moving the shm_may_destroy() check under the appropriate lock to ensure proper serialization. The vulnerability affects specific Linux kernel versions and has been assigned CVE-2026-52930 with a medium severity rating.
References
- ubuntu.com/security/CVE-2026-52930 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-52930 (opens in a new tab)
- git.kernel.org/linus/2e5c6f4fd4001562781e99bbfc7f1f0127187542 (opens in a new tab)
- git.kernel.org/stable/c/030bbc857bd51d4b25a90d931d3f8775ef22823a (opens in a new tab)
- git.kernel.org/stable/c/1f0d01e35dbb228084d5187212e32c91a30dcbeb (opens in a new tab)
- git.kernel.org/stable/c/2e5c6f4fd4001562781e99bbfc7f1f0127187542 (opens in a new tab)
- git.kernel.org/stable/c/6560be3f6a5bb84f006f184f0c966747bb58e1a3 (opens in a new tab)
- git.kernel.org/stable/c/92cda2593cf2ed25b0e9d78e5e6d8303bba1a064 (opens in a new tab)
- git.kernel.org/stable/c/b1e9aef48e4d8a0c1b54fb913077b0824ed7d650 (opens in a new tab)
- git.kernel.org/stable/c/b5107b4ce3ad45fcf369ee2058c8910620f4b5a8 (opens in a new tab)
- git.kernel.org/stable/c/db752ebfdaf2c7f27cd9690ef48b616af068319c (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-52930 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8800-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)