CVE-2026-52927: Linux kernel · netfilter: ebtables: fix OOB read in compat_mtw_from_user
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 12:55 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 +67
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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 released in multiple Linux kernel versions including 5.15.0-1117.124~20.04.1 and later. Users should apply these official kernel updates to remediate the vulnerability. No additional mitigation steps are required beyond applying the vendor-provided patches.
Description
A vulnerability in the Linux kernel's netfilter ebtables subsystem was fixed to prevent an out-of-bounds read caused by improper validation of user-supplied sizes in the compat_mtw_from_user() function. This function converts 32-bit user structures to kernel native structures but lacked checks ensuring the provided match_size is at least as large as the extension's required size. The flaw could lead to memory access beyond intended bounds. The issue affects multiple Linux kernel versions and has been addressed in patched releases.
References
- ubuntu.com/security/CVE-2026-52927 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-52927 (opens in a new tab)
- git.kernel.org/linus/f438d1786d657d57790c5d138d6db3fc9fdac392 (opens in a new tab)
- git.kernel.org/stable/c/21af4c030567d2e6c89bb927bc18b51fba52a400 (opens in a new tab)
- git.kernel.org/stable/c/7ad0e463fc7eafae2141cc38054264636f8b3e94 (opens in a new tab)
- git.kernel.org/stable/c/a27cb7325a6c69970041c7f8541fafed5a1ea3ec (opens in a new tab)
- git.kernel.org/stable/c/bf8e8eac7ede51dc318e06acef5a896dcbba7595 (opens in a new tab)
- git.kernel.org/stable/c/d7a8fb6f10d55a1c37b0bf8c20cca24dffd76e00 (opens in a new tab)
- git.kernel.org/stable/c/dad9ebf8107955bb54bd3f9cf22591b6ff37bac1 (opens in a new tab)
- git.kernel.org/stable/c/f438d1786d657d57790c5d138d6db3fc9fdac392 (opens in a new tab)
- git.kernel.org/stable/c/fcc4c043d137e7f1de4673dba1f3116e45377c67 (opens in a new tab)
- ubuntu.com/security/notices/USN-8566-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8568-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8569-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8603-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8618-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8663-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8664-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)