FKIE_CVE-2020-36430

Vulnerability from fkie_nvd - Published: 2021-07-20 07:15 - Updated: 2026-06-17 03:15
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Summary
libass 0.15.x before 0.15.1 has a heap-based buffer overflow in decode_chars (called from decode_font and process_text) because the wrong integer data type is used for subtraction.
References
cve@mitre.orghttps://bugs.chromium.org/p/oss-fuzz/issues/detail?id=26674Issue Tracking, Patch, Third Party Advisory
cve@mitre.orghttps://github.com/google/oss-fuzz-vulns/blob/main/vulns/libass/OSV-2020-2099.yamlThird Party Advisory
cve@mitre.orghttps://github.com/libass/libass/commit/017137471d0043e0321e377ed8da48e45a3ec632Patch, Third Party Advisory
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6JUXFQUJ32GWG5E46A63DFDCYJAF3VU6/
cve@mitre.orghttps://security.gentoo.org/glsa/202208-13Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=26674Issue Tracking, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/google/oss-fuzz-vulns/blob/main/vulns/libass/OSV-2020-2099.yamlThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/libass/libass/commit/017137471d0043e0321e377ed8da48e45a3ec632Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6JUXFQUJ32GWG5E46A63DFDCYJAF3VU6/
af854a3a-2127-422b-91ae-364da2661108https://security.gentoo.org/glsa/202208-13Third Party Advisory
Impacted products
Vendor Product Version
libass_project libass *
fedoraproject fedora 34
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:libass_project:libass:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "7EA27EE0-8263-449D-B512-5BB4FBB2FF05",
              "versionEndExcluding": "0.15.1",
              "versionStartIncluding": "0.15.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*",
              "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "libass 0.15.x before 0.15.1 has a heap-based buffer overflow in decode_chars (called from decode_font and process_text) because the wrong integer data type is used for subtraction."
    },
    {
      "lang": "es",
      "value": "libass versiones 0.15.x anteriores a 0.15.1, presenta un desbordamiento de b\u00fafer en la regi\u00f3n heap de la memoria en la funci\u00f3n decode_chars (llamado desde decode_font y process_text) porque es usado el tipo de datos entero incorrecto para la sustracci\u00f3n"
    }
  ],
  "id": "CVE-2020-36430",
  "lastModified": "2026-06-17T03:15:28.513",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 6.8,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 8.6,
        "impactScore": 6.4,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": true
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-07-20T07:15:07.817",
  "references": [
    {
      "source": "cve@mitre.org",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=26674"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://github.com/google/oss-fuzz-vulns/blob/main/vulns/libass/OSV-2020-2099.yaml"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
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      ],
      "url": "https://github.com/libass/libass/commit/017137471d0043e0321e377ed8da48e45a3ec632"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6JUXFQUJ32GWG5E46A63DFDCYJAF3VU6/"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.gentoo.org/glsa/202208-13"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Issue Tracking",
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=26674"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://github.com/google/oss-fuzz-vulns/blob/main/vulns/libass/OSV-2020-2099.yaml"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/libass/libass/commit/017137471d0043e0321e377ed8da48e45a3ec632"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6JUXFQUJ32GWG5E46A63DFDCYJAF3VU6/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.gentoo.org/glsa/202208-13"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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