CVE-2026-89731: Linux kernel · cxl/ras: Fix cxl_rch_get_aer_info() out-of-bounds AER register read
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Sep 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
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 that corrects the out-of-bounds read by bounding the memory read to the physical AER register size and zeroing the destination buffer. Users should apply the official Linux kernel updates that include this patch for the affected versions. No additional mitigations are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's cxl/ras component caused an out-of-bounds read of the AER register block due to a mismatch between the software struct size and the physical register size. This could lead to out-of-bounds memory reads and potential denial of service. The issue has been resolved by bounding the read to the physical AER registers and zeroing the destination buffer to prevent reading software-only fields.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89731 (opens in a new tab)
- git.kernel.org/stable/c/29458e62d0829cbc99435f3e44fd560f9bbf1da7 (opens in a new tab)
- git.kernel.org/stable/c/8bd3523df1319edc61cd391e695c84a4618516df (opens in a new tab)
- git.kernel.org/stable/c/8e3d9dbb25d3ddbe72b4542ec4f7c4e622fe0ced (opens in a new tab)
- ubuntu.com/security/CVE-2026-89731 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89731 (opens in a new tab)
- git.kernel.org/linus/29458e62d0829cbc99435f3e44fd560f9bbf1da7 (opens in a new tab)