CVE-2026-89445

In the Linux kernel, the following vulnerability has been resolved: iommufd: Fix UAF in selftest IOPF reporting IOMMUFD selftest TRIGGER_IOPF borrows an attach handle from group->pasid_array without synchronizing against PASID detach, then a concurrent iommu_report_device_fault() can dereference that borrowed handle's domain pointer after the detach erases the handle and frees the backing struct iommufd_attach_handle. TRIGGER_IOPF then dereferences the freed handle, causing a UAF. Fix by adding a iopf_rwsem in mock_dev to follow the expected design of a real driver. Hold its read side across the whole iommu_report_device_fault() call, and its write side around every path that attaches, detaches, or replaces a device domain. This can block new reports and drains in-flight reports before an old attach handle or the IOPF fault parameter can be removed. Also take the write side while registering a mock device, since it can invoke the mock driver's default-domain attach callback.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.0 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://git.kernel.org/stable/c/8c07df7cdfcf52f1ff276c588612aabc6c6b8399
https://git.kernel.org/stable/c/cab2895729516799384d48560e6fca105fb3f927
https://git.kernel.org/stable/c/e27e90bde68b2ab92e63ed19caad1ef57188bea0

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 20:19

Updated : 2026-09-13 07:17

NVD link : CVE-2026-89445

Mitre link : CVE-2026-89445

CVE.ORG link : CVE-2026-89445

JSON object : View

Products Affected

No product.

CWE

No CWE.

{"id": "CVE-2026-89445", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 6.0, "exploitabilityScore": 2.0}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "ddee19971081b42615d62f4fdada21274708ed4d", "lessThan": "cab2895729516799384d48560e6fca105fb3f927", "versionType": "git"}, {"status": "affected", "version": "ddee19971081b42615d62f4fdada21274708ed4d", "lessThan": "e27e90bde68b2ab92e63ed19caad1ef57188bea0", "versionType": "git"}, {"status": "affected", "version": "ddee19971081b42615d62f4fdada21274708ed4d", "lessThan": "8c07df7cdfcf52f1ff276c588612aabc6c6b8399", "versionType": "git"}], "programFiles": ["drivers/iommu/iommufd/selftest.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.11"}, {"status": "unaffected", "version": "0", "lessThan": "6.11", "versionType": "semver"}, {"status": "unaffected", "version": "6.18.50", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.2.4", "versionType": "semver", "lessThanOrEqual": "7.2.*"}, {"status": "unaffected", "version": "7.3-rc1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["drivers/iommu/iommufd/selftest.c"], "defaultStatus": "affected"}]}], "published": "2026-09-11T20:19:24.990", "references": [{"url": "https://git.kernel.org/stable/c/8c07df7cdfcf52f1ff276c588612aabc6c6b8399", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/cab2895729516799384d48560e6fca105fb3f927", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e27e90bde68b2ab92e63ed19caad1ef57188bea0", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Received", "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommufd: Fix UAF in selftest IOPF reporting\n\nIOMMUFD selftest TRIGGER_IOPF borrows an attach handle from\ngroup->pasid_array without synchronizing against PASID detach,\nthen a concurrent iommu_report_device_fault() can dereference\nthat borrowed handle's domain pointer after the detach erases\nthe handle and frees the backing struct iommufd_attach_handle.\nTRIGGER_IOPF then dereferences the freed handle, causing a UAF.\n\nFix by adding a iopf_rwsem in mock_dev to follow the expected design\nof a real driver. Hold its read side across the whole\niommu_report_device_fault() call, and its write side around every\npath that attaches, detaches, or replaces a device domain.\nThis can block new reports and drains in-flight reports before an old\nattach handle or the IOPF fault parameter can be removed.\nAlso take the write side while registering a mock device, since\nit can invoke the mock driver's default-domain attach callback."}], "lastModified": "2026-09-13T07:17:09.093", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}