UnratedFix available

libass vulnerabilities

Type: advisorySource: OSV1 source record

It was discovered that libass incorrectly handled parsing operations for specific nested character strings. An attacker could use this issue to cause libass to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2020-24994) It was discovered that libass incorrectly handled certain outline processing operations. An attacker could use this issue to cause libass to crash, resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2020-26682) It was discovered that libass incorrectly handled certain ASS subtitle files when measuring wrapped lines. An attacker could use this issue to cause libass to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-61627) It was discovered that libass incorrectly handled certain Matroska subtitle chunks with negative ReadOrder values. An attacker could use this issue to cause libass to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-61626)

Announced 24 Sept 2026Group revision 1

Original source ↗

USN-8815-1

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:USN-8815-1

libass

Source reference: /affected/0/package/name

Affected versions: 0.10.1-1ubuntu1
Source reference: /affected/0/versions
0.10.1-3
Source reference: /affected/0/versions
0.10.1-3ubuntu1
Source reference: /affected/0/versions
0.10.1-3ubuntu1+esm1
Source reference: /affected/0/versions
Fixed versions: 0.10.1-3ubuntu1+esm2
Source reference: /affected/0/ranges
Prerequisites: Not stated in this record

libass

Source reference: /affected/1/package/name

Affected versions: 1:0.13.7-2
Source reference: /affected/1/versions
1:0.14.0-1
Source reference: /affected/1/versions
Fixed versions: 1:0.14.0-1ubuntu0.1~esm1
Source reference: /affected/1/ranges
Prerequisites: Not stated in this record

libass

Source reference: /affected/2/package/name

Affected versions: 1:0.14.0-2
Source reference: /affected/2/versions
Fixed versions: 1:0.14.0-2ubuntu0.1~esm1
Source reference: /affected/2/ranges
Prerequisites: Not stated in this record

libass

Source reference: /affected/3/package/name

Affected versions: 1:0.17.1-1
Source reference: /affected/3/versions
1:0.17.1-2
Source reference: /affected/3/versions
1:0.17.1-2build1
Source reference: /affected/3/versions
Fixed versions: 1:0.17.1-2ubuntu0.1~esm1
Source reference: /affected/3/ranges
Prerequisites: Not stated in this record

libass

Source reference: /affected/4/package/name

Affected versions: 1:0.17.3-1
Source reference: /affected/4/versions
1:0.17.4-2
Source reference: /affected/4/versions
Fixed versions: 1:0.17.4-2ubuntu0.1~esm1
Source reference: /affected/4/ranges
Prerequisites: Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

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          {
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          }
        ]
      }
    ],
    "package": {
      "name": "libass",
      "purl": "pkg:deb/ubuntu/libass?arch=source&distro=esm-infra-legacy%2Ftrusty",
      "ecosystem": "Ubuntu:Pro:14.04:LTS"
    },
    "versions": [
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      "0.10.1-3",
      "0.10.1-3ubuntu1",
      "0.10.1-3ubuntu1+esm1"
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        ],
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    "ecosystem_specific": {
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          "binary_name": "libass4",
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    "package": {
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          {
            "id": "CVE-2020-26682",
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              },
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              }
            ]
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        ],
        "ecosystem": "Ubuntu:Pro:18.04:LTS"
      }
    },
    "ecosystem_specific": {
      "binaries": [
        {
          "binary_name": "libass9",
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  },
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        ]
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    ],
    "package": {
      "name": "libass",
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      "ecosystem": "Ubuntu:Pro:20.04:LTS"
    },
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      "1:0.14.0-2"
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              },
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          {
            "id": "CVE-2020-26682",
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              },
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                "type": "Ubuntu",
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              }
            ]
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        ],
        "ecosystem": "Ubuntu:Pro:20.04:LTS"
      }
    },
    "ecosystem_specific": {
      "binaries": [
        {
          "binary_name": "libass9",
          "binary_version": "1:0.14.0-2ubuntu0.1~esm1"
        }
      ],
      "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "1:0.17.1-2ubuntu0.1~esm1"
          }
        ]
      }
    ],
    "package": {
      "name": "libass",
      "purl": "pkg:deb/ubuntu/libass?arch=source&distro=esm-apps%2Fnoble",
      "ecosystem": "Ubuntu:Pro:24.04:LTS"
    },
    "versions": [
      "1:0.17.1-1",
      "1:0.17.1-2",
      "1:0.17.1-2build1"
    ],
    "database_specific": {
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      "cves_map": {
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            "id": "CVE-2026-61627",
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              }
            ]
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        ],
        "ecosystem": "Ubuntu:Pro:24.04:LTS"
      }
    },
    "ecosystem_specific": {
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        {
          "binary_name": "libass9",
          "binary_version": "1:0.17.1-2ubuntu0.1~esm1"
        }
      ],
      "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro"
    }
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        ]
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    "package": {
      "name": "libass",
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      "ecosystem": "Ubuntu:Pro:26.04:LTS"
    },
    "versions": [
      "1:0.17.3-1",
      "1:0.17.4-2"
    ],
    "database_specific": {
      "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8815-1.json",
      "cves_map": {
        "cves": [
          {
            "id": "CVE-2026-61626",
            "severity": [
              {
                "type": "Ubuntu",
                "score": "medium"
              }
            ]
          },
          {
            "id": "CVE-2026-61627",
            "severity": [
              {
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                "score": "medium"
              }
            ]
          }
        ],
        "ecosystem": "Ubuntu:Pro:26.04:LTS"
      }
    },
    "ecosystem_specific": {
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        {
          "binary_name": "libass9",
          "binary_version": "1:0.17.4-2ubuntu0.1~esm1"
        }
      ],
      "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro"
    }
  }
]

Publisher severity

No explicit severity was provided.

Event: #14647 · Revision 1
Added to Heist Feed: Sun, 25 Oct 2026 00:45:30 GMT
Publisher date: Thu, 24 Sep 2026 14:57:46 GMT

Read the original announcement

Revision history

25 Oct 2026USN-8815-1 · Revision 1Source updated