CVE-2026-74573 (GCVE-0-2026-74573)

Vulnerability from cvelistv5 – Published: 2026-08-15 12:28 – Updated: 2026-10-16 19:05
VLAI
Title
iommu/arm-smmu-v3-iommufd: Require exactly one Stream ID for a vDEVICE
Summary
In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu-v3-iommufd: Require exactly one Stream ID for a vDEVICE arm_vsmmu_vsid_to_sid() maps a guest's vSID to a single physical Stream ID taken from master->streams[0], assuming a device has exactly one stream. A device with several streams gets only its first one mapped, so a guest vSID invalidation cannot reach the others' ATC and IOTLB entries; a device with none makes master->streams a ZERO_SIZE_PTR, read out of bounds. Add an arm_vsmmu_vdevice_init() op to reject the vDEVICE with -EOPNOTSUPP when master->num_streams is not one, rather than mapping it silently.
Severity
9.3 (Critical)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 19:00 UTC
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6992 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: d68beb276ba26cec47350a6d468e967673ee0c56 , < 3808bab5d95ae79e333e11f6a73d178e084c645d (git)
Affected: d68beb276ba26cec47350a6d468e967673ee0c56 , < 0acbc621341aca4eb94d9c2f43e1ab273ff088f0 (git)
Affected: d68beb276ba26cec47350a6d468e967673ee0c56 , < c3b8ee84a965058b41275069d4696f37a8b14bf6 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.13
Unaffected: 0 , < 6.13 (semver)
Unaffected: 6.18.44 , ≤ 6.18.* (semver)
Unaffected: 7.1.8 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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      "cve": "CVE-2026-74573",
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      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74573.json",
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}



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