CVE-2026-53281
Vulnerability Summary
Timeline
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
CVSS Metrics
- v3.1•HIGH•Score: 8.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS Trends
Current EPSS score: 0.13%• Percentile: 3%
Techniques & Countermeasures
- CWE-476•NULL Pointer Dereference
The product dereferences a pointer that it expects to be valid but is NULL.
Affected Systems
- chainguard•linux-aws-6.12
all
- chainguard•linux-azure-6.12
all
- chainguard•linux-gcp-6.12
all
- chainguard•linux-qemu-6.12
all
- chainguard•linux-vmware-6.12
all
- debian•linux
all | < 7.0.10-1
- ubuntu•linux
all | all | < 7.0.0-28.28
- ubuntu•linux-allwinner-5.19
all
- ubuntu•linux-aws
all | all | < 7.0.0-1009.9
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.11
all
- ubuntu•linux-aws-5.13
all
- ubuntu•linux-aws-5.19
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.8
all
- ubuntu•linux-aws-6.14
all
- ubuntu•linux-aws-6.17
all
- ubuntu•linux-aws-6.2
all
- ubuntu•linux-aws-6.5
all
- ubuntu•linux-aws-6.8
all
- ubuntu•linux-aws-fips
all
- ubuntu•linux-azure
all | all | all | < 7.0.0-1010.10
- ubuntu•linux-azure-5.11
all
- ubuntu•linux-azure-5.13
all
- ubuntu•linux-azure-5.19
all
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.8
all
- ubuntu•linux-azure-6.11
all
- ubuntu•linux-azure-6.14
all
- ubuntu•linux-azure-6.17
all
- ubuntu•linux-azure-6.2
all
- ubuntu•linux-azure-6.5
all
- ubuntu•linux-azure-6.8
all
- ubuntu•linux-azure-7.0
all
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fde
all | all | all | < 7.0.0-1009.9
- ubuntu•linux-azure-fde-5.19
all
- ubuntu•linux-azure-fde-6.14
all
- ubuntu•linux-azure-fde-6.17
all
- ubuntu•linux-azure-fde-6.2
all
- ubuntu•linux-azure-fde-6.8
all
- ubuntu•linux-azure-fips
all
- ubuntu•linux-azure-nvidia
all
- ubuntu•linux-azure-nvidia-6.14
all
- ubuntu•linux-bluefield
all
- ubuntu•linux-fips
all
- ubuntu•linux-gcp
all | all | all | < 7.0.0-1008.8
- ubuntu•linux-gcp-5.11
all
- ubuntu•linux-gcp-5.13
all
- ubuntu•linux-gcp-5.19
all
Showing first 50 affected entries in server-rendered view.
References (24)
- https://git.kernel.org/stable/c/9022cb9ac0c2a72a57fa8ebf92ac74f953ca0153
- https://git.kernel.org/stable/c/cdfe3c9f2c9e28a8651ee463c88ad191ced2f840
- https://git.kernel.org/stable/c/79ea2feb917b05366b49d85573c9c5331f043b2c
- https://access.redhat.com/security/cve/CVE-2026-53281
- https://bugzilla.redhat.com/show_bug.cgi?id=2493728
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53281.json
- https://access.redhat.com/errata/RHSA-2026:47017
- https://access.redhat.com/errata/RHSA-2026:47040
- https://ubuntu.com/security/CVE-2026-53281
- https://www.cve.org/CVERecord?id=CVE-2026-53281
- https://git.kernel.org/linus/79ea2feb917b05366b49d85573c9c5331f043b2c
- https://ubuntu.com/security/notices/USN-8566-1
- https://ubuntu.com/security/notices/USN-8568-1
- https://ubuntu.com/security/notices/USN-8569-1
- https://ubuntu.com/security/notices/USN-8593-1
- https://ubuntu.com/security/notices/USN-8603-1
- https://ubuntu.com/security/notices/USN-8618-1
- https://security-tracker.debian.org/tracker/CVE-2026-53281
- https://ubuntu.com/security/notices/USN-8663-1
- https://ubuntu.com/security/notices/USN-8664-1
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53281.json
- https://nvd.nist.gov/vuln/detail/CVE-2026-53281
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://ubuntu.com/security/notices/USN-8728-1