CVE-2026-63849 (GCVE-0-2026-63849)
Vulnerability from cvelistv5
Published
2026-07-19 14:04
Modified
2026-10-19 20:07
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/vcn: set no_user_fence for VCN v5.0.1 enc ring VCN encoder and decoder rings do not support 64-bit user fence writes, reject CS submissions with user fences. (cherry picked from commit e16be95a2c3ee712b142cb27d2dca0b461181359)
References
Impacted products
Vendor Product Version
Linux Linux Version: 346492f30ce3581bf5324c4ae417eab8537dc998
Version: 346492f30ce3581bf5324c4ae417eab8537dc998
Version: 346492f30ce3581bf5324c4ae417eab8537dc998
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-63849",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-16T15:32:07.985488Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-20",
                "description": "CWE-20 Improper Input Validation",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-10-19T20:07:51.086Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/amd/amdgpu/vcn_v5_0_1.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "081ef0e46c9cdd26c0db0ef721470393d36b6655",
              "status": "affected",
              "version": "346492f30ce3581bf5324c4ae417eab8537dc998",
              "versionType": "git"
            },
            {
              "lessThan": "5a4bffd67e94944ed3db26a959346cfb7fabaecd",
              "status": "affected",
              "version": "346492f30ce3581bf5324c4ae417eab8537dc998",
              "versionType": "git"
            },
            {
              "lessThan": "8f4954722eab88e10c4ea0c0d3b1269c31421d3a",
              "status": "affected",
              "version": "346492f30ce3581bf5324c4ae417eab8537dc998",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/amd/amdgpu/vcn_v5_0_1.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.14"
            },
            {
              "lessThan": "6.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.33",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.33",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.10",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu/vcn: set no_user_fence for VCN v5.0.1 enc ring\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 e16be95a2c3ee712b142cb27d2dca0b461181359)"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The vulnerability is reached only through local DRM ioctls (primarily DRM_IOCTL_AMDGPU_CS on a /dev/dri/renderD* node), not over any network protocol.\nAC:L - An attacker with render-node access can deterministically submit a VCN_ENC command buffer with an AMDGPU_CHUNK_ID_FENCE chunk; no race or attacker-uncontrollable conditions are required beyond having the affected AMDGPU hardware.\nPR:L - Exploitation requires only local access to the GPU render node as an unprivileged user (DRM_AUTH|DRM_RENDER_ALLOW); no root or special capabilities are needed.\nUI:N - Triggering the bug requires only the attacker\u0027s own ioctl submissions; no action by another user or victim is required.\nS:U - Impact is confined to the attacker\u0027s GPU command-submission context and process GPU virtual address space; it does not cross a VM/host or other security-boundary scope.\nC:H - The unsupported 64-bit user-fence path causes the VCN engine to perform GPU memory writes to attacker-influenced addresses, which constitutes exploitable memory corruption that can be leveraged for information disclosure.\nI:H - The malformed fence write gives the attacker a GPU-initiated arbitrary memory write primitive within their GPU VA space, which can corrupt adjacent buffers and be chained toward code execution.\nA:H - Submitting unsupported user fences to the VCN ring can hang or reset the GPU and trigger kernel driver errors, causing denial of service on affected systems."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:36:27.366Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/081ef0e46c9cdd26c0db0ef721470393d36b6655"
        },
        {
          "url": "https://git.kernel.org/stable/c/5a4bffd67e94944ed3db26a959346cfb7fabaecd"
        },
        {
          "url": "https://git.kernel.org/stable/c/8f4954722eab88e10c4ea0c0d3b1269c31421d3a"
        }
      ],
      "title": "drm/amdgpu/vcn: set no_user_fence for VCN v5.0.1 enc ring",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-63849",
    "datePublished": "2026-07-19T14:04:41.395Z",
    "dateReserved": "2026-07-19T07:54:57.016Z",
    "dateUpdated": "2026-10-19T20:07:51.086Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-63849\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-10-16T15:32:07.985488Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-20\", \"description\": \"CWE-20 Improper Input Validation\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-10-16T15:32:08.570Z\"}}], \"cna\": {\"title\": \"drm/amdgpu/vcn: set no_user_fence for VCN v5.0.1 enc ring\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 7.8, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:L - The vulnerability is reached only through local DRM ioctls (primarily DRM_IOCTL_AMDGPU_CS on a /dev/dri/renderD* node), not over any network protocol.\\nAC:L - An attacker with render-node access can deterministically submit a VCN_ENC command buffer with an AMDGPU_CHUNK_ID_FENCE chunk; no race or attacker-uncontrollable conditions are required beyond having the affected AMDGPU hardware.\\nPR:L - Exploitation requires only local access to the GPU render node as an unprivileged user (DRM_AUTH|DRM_RENDER_ALLOW); no root or special capabilities are needed.\\nUI:N - Triggering the bug requires only the attacker\u0027s own ioctl submissions; no action by another user or victim is required.\\nS:U - Impact is confined to the attacker\u0027s GPU command-submission context and process GPU virtual address space; it does not cross a VM/host or other security-boundary scope.\\nC:H - The unsupported 64-bit user-fence path causes the VCN engine to perform GPU memory writes to attacker-influenced addresses, which constitutes exploitable memory corruption that can be leveraged for information disclosure.\\nI:H - The malformed fence write gives the attacker a GPU-initiated arbitrary memory write primitive within their GPU VA space, which can corrupt adjacent buffers and be chained toward code execution.\\nA:H - Submitting unsupported user fences to the VCN ring can hang or reset the GPU and trigger kernel driver errors, causing denial of service on affected systems.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"346492f30ce3581bf5324c4ae417eab8537dc998\", \"lessThan\": \"081ef0e46c9cdd26c0db0ef721470393d36b6655\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"346492f30ce3581bf5324c4ae417eab8537dc998\", \"lessThan\": \"5a4bffd67e94944ed3db26a959346cfb7fabaecd\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"346492f30ce3581bf5324c4ae417eab8537dc998\", \"lessThan\": \"8f4954722eab88e10c4ea0c0d3b1269c31421d3a\", \"versionType\": \"git\"}], \"programFiles\": [\"drivers/gpu/drm/amd/amdgpu/vcn_v5_0_1.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"6.14\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"6.14\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"6.18.33\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.18.*\"}, {\"status\": \"unaffected\", \"version\": \"7.0.10\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"7.0.*\"}, {\"status\": \"unaffected\", \"version\": \"7.1\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"drivers/gpu/drm/amd/amdgpu/vcn_v5_0_1.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/081ef0e46c9cdd26c0db0ef721470393d36b6655\"}, {\"url\": \"https://git.kernel.org/stable/c/5a4bffd67e94944ed3db26a959346cfb7fabaecd\"}, {\"url\": \"https://git.kernel.org/stable/c/8f4954722eab88e10c4ea0c0d3b1269c31421d3a\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\ndrm/amdgpu/vcn: set no_user_fence for VCN v5.0.1 enc ring\\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 e16be95a2c3ee712b142cb27d2dca0b461181359)\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.18.33\", \"versionStartIncluding\": \"6.14\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.0.10\", \"versionStartIncluding\": \"6.14\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.1\", \"versionStartIncluding\": \"6.14\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-08-05T12:36:27.366Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-63849\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-10-19T20:07:51.086Z\", \"dateReserved\": \"2026-07-19T07:54:57.016Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2026-07-19T14:04:41.395Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.