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CVE-2026-63855

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vcn: set no_user_fence for VCN v2.5 enc/dec rings VCN encoder and decoder rings do not support 64-bit user fence writes, reject CS submissions with user fences. (cherry picked from commit efc9dd5590894109bce9a0bfe1fa5592dd6b20b1)

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-19 15:16:52.337000
Last modified
2026-10-30 13:19:21.533000
View original CVE JSON 
{
  "id": "CVE-2026-63855",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-19T15:16:52.337",
  "lastModified": "2026-10-30T13:19:21.533",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu/vcn: set no_user_fence for VCN v2.5 enc/dec rings\n\nVCN encoder and decoder rings do not support 64-bit user fence writes,\nreject CS submissions with user fences.\n\n(cherry picked from commit efc9dd5590894109bce9a0bfe1fa5592dd6b20b1)"
    }
  ],
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      "affectedData": [
        {
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          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/gpu/drm/amd/amdgpu/vcn_v2_5.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
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          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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              "version": "7.0.10",
              "lessThanOrEqual": "7.0.*",
              "versionType": "semver",
              "status": "unaffected"
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              "version": "7.1",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
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        "exploitabilityScore": 1.8,
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    ],
    "ssvcV203": [
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          "role": "CISA Coordinator",
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  "weaknesses": [
    {
      "source": "[email protected]",
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      "description": [
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  ],
  "configurations": [
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}