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CVE-2026-43220

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: iommu/amd: serialize sequence allocation under concurrent TLB invalidations With concurrent TLB invalidations, completion wait randomly gets timed out because cmd_sem_val was incremented outside the IOMMU spinlock, allowing CMD_COMPL_WAIT commands to be queued out of sequence and breaking the ordering assumption in wait_on_sem(). Move the cmd_sem_val increment under iommu->lock so completion sequence allocation is serialized with command queuing. And remove the unnecessary return.

Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-06 12:16:41.660000
Last modified
2026-10-30 13:18:48.200000
View original CVE JSON 
{
  "id": "CVE-2026-43220",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-05-06T12:16:41.660",
  "lastModified": "2026-10-30T13:18:48.200",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/amd: serialize sequence allocation under concurrent TLB invalidations\n\nWith concurrent TLB invalidations, completion wait randomly gets timed out\nbecause cmd_sem_val was incremented outside the IOMMU spinlock, allowing\nCMD_COMPL_WAIT commands to be queued out of sequence and breaking the\nordering assumption in wait_on_sem().\nMove the cmd_sem_val increment under iommu->lock so completion sequence\nallocation is serialized with command queuing.\nAnd remove the unnecessary return."
    }
  ],
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
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        "exploitabilityScore": 1.8,
        "impactScore": 3.6
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  "weaknesses": [
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