CVE-2026-64186: Linux kernel · iommu/amd: Remove latent out-of-bounds access in IOMMU debugfs
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High · fixed in 7.0.0-28.28~24.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 16:08 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.
- Patch
- Available – fixed in 7.0.0-28.28~24.04.1, 7.0.0-1016.16~24.04.1, 7.0.0-28.28 +12
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 20 Jul 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 by updating the Linux kernel to the fixed versions at or beyond 7.0.0-28.28.1 or the specific patched versions listed in the advisory. After updating, a system reboot is required to apply the fixes. Due to ABI changes, third-party kernel modules must be recompiled and reinstalled. Follow the vendor's update instructions carefully. No additional mitigation actions are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's AMD IOMMU debugfs implementation (CVE-2026-64186) involved latent out-of-bounds access due to improper handling of signed integer conversion from user input. This could potentially lead to memory corruption or denial of service. The issue was addressed by correcting the parsing function to properly handle signed integers. The vulnerability affects multiple Linux kernel versions prior to 7.0.0-28.28.1 and specific listed versions. A patch is available and should be applied to mitigate the issue.
References
- ubuntu.com/security/CVE-2026-64186 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-64186 (opens in a new tab)
- git.kernel.org/linus/8dfd3d8d74435344ee8dc9237596959c8b2a6cbe (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)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-3 (opens in a new tab)