CVE-2026-64290: Linux kernel · iommufd: Break the loop on failure in iommufd_fault_fops_read()
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in f66c16b175509642ee7082df57c9bf3deaebae1a : update Linux kernel when convenient.
Data as of 6 Nov 2026, 16:51 UTC
Rated Medium by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-06.
- Patch
- Available – fixed in f66c16b175509642ee7082df57c9bf3deaebae1a, a38e0714affc5c0bbb40cba5a65d6d32a5e72a71, 5539da127d03c1f6c2e2a49fdfbe331a0ccbdea8 +1
Exploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 6 Nov 2026.
What to do
Upgrade Linux kernel to f66c16b175509642ee7082df57c9bf3deaebae1a, a38e0714affc5c0bbb40cba5a65d6d32a5e72a71, 5539da127d03c1f6c2e2a49fdfbe331a0ccbdea8 or 172fc8b19825a0f5884c38f2289188284e2d45ee.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix is available in the Linux kernel versions identified by the fixed commit hashes. Users should update to a kernel version that includes these fixes to resolve the issue.
Description
A vulnerability in the Linux kernel's iommufd component caused an infinite retry loop on copy_to_user() failures in the iommufd_fault_fops_read() function. This loop spun the CPU at 100% while holding a mutex, potentially causing a denial of service. The issue was fixed by breaking the outer loop on failure to prevent indefinite retries.
References
- git.kernel.org/stable/c/a38e0714affc5c0bbb40cba5a65d6d32a5e72a71 (opens in a new tab)
- git.kernel.org/stable/c/5539da127d03c1f6c2e2a49fdfbe331a0ccbdea8 (opens in a new tab)
- git.kernel.org/stable/c/f66c16b175509642ee7082df57c9bf3deaebae1a (opens in a new tab)
- git.kernel.org/stable/c/172fc8b19825a0f5884c38f2289188284e2d45ee (opens in a new tab)