CVE-2026-53281: Linux kernel · iommu/vt-d: Avoid NULL pointer dereference or refcount corruption
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 8.8 High · fixed in d1a677f9c5e02c4ae49614044ac21296660d1391 : patch Linux kernel soon.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- 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
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in d1a677f9c5e02c4ae49614044ac21296660d1391, cdfe3c9f2c9e28a8651ee463c88ad191ced2f840, 9022cb9ac0c2a72a57fa8ebf92ac74f953ca0153 +3
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 26 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 |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Avoid NULL pointer dereference or refcount corruption Commit 60f030f7418d ("iommu/vt-d: Avoid use of NULL after WARN_ON_ONCE") fixed a NULL pointer dereference in an unlikely situation partly. If dev_pasid is not found in the dev_pasids list, it remains NULL. However, the teardown operations are executed unconditionally, this lead to a NULL pointer dereference or refcount corruption. If the domain was never attached to this IOMMU, info will be NULL, which would cause an immediate dereference when checking --info->refcnt. Even if info is not NULL, decrementing the refcount without having removed a valid PASID might unbalance the count. This could lead to premature dropping of the refcount to 0, potentially causing a use-after-free for the remaining active devices sharing the domain. Fix it by returning early if dev_pasid is NULL, before executing the teardown operations. Issue found by AI review and suggested by Kevin Tian. https://sashiko.dev/#/patchset/20260421031347.1408890-1-zhenzhong.duan%40intel.com
References
- git.kernel.org/stable/c/d1a677f9c5e02c4ae49614044ac21296660d1391 (opens in a new tab)
- git.kernel.org/stable/c/9022cb9ac0c2a72a57fa8ebf92ac74f953ca0153 (opens in a new tab)
- git.kernel.org/stable/c/cdfe3c9f2c9e28a8651ee463c88ad191ced2f840 (opens in a new tab)
- git.kernel.org/stable/c/79ea2feb917b05366b49d85573c9c5331f043b2c (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-53281 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2493728 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53281.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:47017 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:47040 (opens in a new tab)