CVE-2026-64186: Linux kernel · iommu/amd: Remove latent out-of-bounds access in IOMMU debugfs
Source 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 19 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
AI-suggested
A patch has been applied to the Linux kernel that replaces the unsigned integer parsing function with a signed integer parser and adds explicit checks to prevent negative values, effectively mitigating the vulnerability. Users should update to the fixed kernel version once available. Since this is a kernel-level vulnerability, applying the official kernel update from the vendor or distribution is the recommended remediation. Patch status is not explicitly stated in the input data; check the vendor advisory for current remediation guidance.
Description
A high-severity vulnerability (CVE-2026-64186) in the Linux kernel's AMD IOMMU debugfs interface allowed out-of-bounds memory access due to improper handling of signed integer conversion. The flaw involved variables declared as int but populated from user input parsed as unsigned, which could lead to negative values and potential memory corruption. The issue was addressed by changing the input parsing function to handle signed integers and adding explicit checks to prevent negative values.
References
- nvd.nist.gov/vuln/detail/CVE-2026-64186 (opens in a new tab)
- git.kernel.org/stable/c/488d2c76bd9f78433a70690d1054bfae3d39a407 (opens in a new tab)
- git.kernel.org/stable/c/62f9dfbf1aceae88b03c5ca08f7d36e943939dec (opens in a new tab)
- git.kernel.org/stable/c/8dfd3d8d74435344ee8dc9237596959c8b2a6cbe (opens in a new tab)