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CVE-2026-74449

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix divide-by-zero in calculate_mcache_setting on zero viewport If a plane reaches calculate_mcache_setting with a zero-area viewport, calculate_mcache_setting exits early with num_mcaches == 0 and mvmpg_width/height == 0. This will cause a divide-by-zero panic and can also cause an underflow on num_mcaches. Fix this by changing calculate_mcache_setting to bool and adding guards after each calculate_mcache_row_bytes call. If num_mcaches or mvmpg_width/height is zero, return a false. Callers will propagate the failure as a rejected mode, which prevents the panic. (cherry picked from commit 29c0f7c655f47bcbd575ff75e58480df6ec3c9da)

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-15 13:17:49.500000
Last modified
2026-10-21 13:19:44.547000
View original CVE JSON
{
  "id": "CVE-2026-74449",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-15T13:17:49.500",
  "lastModified": "2026-10-21T13:19:44.547",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amd/display: Fix divide-by-zero in calculate_mcache_setting on zero viewport\n\nIf a plane reaches calculate_mcache_setting with a zero-area viewport,\ncalculate_mcache_setting exits early with num_mcaches == 0 and\nmvmpg_width/height == 0. This will cause a divide-by-zero panic and can\nalso cause an underflow on num_mcaches.\n\nFix this by changing calculate_mcache_setting to bool and adding guards\nafter each calculate_mcache_row_bytes call. If num_mcaches or\nmvmpg_width/height is zero, return a false. Callers will propagate the\nfailure as a rejected mode, which prevents the panic.\n\n(cherry picked from commit 29c0f7c655f47bcbd575ff75e58480df6ec3c9da)"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_core/dml2_core_dcn4_calcs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "70839da6360500a82e4d5f78499284474cbed7c1",
              "lessThan": "70f5f4ddba0d2d89e77ec13b79cdcfbef33be0d9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "70839da6360500a82e4d5f78499284474cbed7c1",
              "lessThan": "23a541c31b45fa813b33269376f6bd53535429a8",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "70839da6360500a82e4d5f78499284474cbed7c1",
              "lessThan": "1f93537881fd22712732a60ad12572a3fd40c0ec",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "70839da6360500a82e4d5f78499284474cbed7c1",
              "lessThan": "f327e389c07cfc3a2f6ff54f6214e1a52d457edc",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_core/dml2_core_dcn4_calcs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.11",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.11",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.114",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.57",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.8",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "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"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T18:56:48.300764Z",
          "id": "CVE-2026-74449",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1f93537881fd22712732a60ad12572a3fd40c0ec",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/23a541c31b45fa813b33269376f6bd53535429a8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/70f5f4ddba0d2d89e77ec13b79cdcfbef33be0d9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f327e389c07cfc3a2f6ff54f6214e1a52d457edc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}