{"id":"USN-8815-1","summary":"libass vulnerabilities","details":"It was discovered that libass incorrectly handled parsing operations for\nspecific nested character strings. An attacker could use this issue to\ncause libass to crash, resulting in a denial of service, or possibly\nexecute arbitrary code. This issue only affected Ubuntu 14.04 LTS,\nUbuntu 16.04 LTS, Ubuntu 18.04 LTS and Ubuntu 20.04 LTS.\n(CVE-2020-24994)\n\nIt was discovered that libass incorrectly handled certain outline\nprocessing operations. An attacker could use this issue to cause libass\nto crash, resulting in a denial of service. This issue only affected\nUbuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2020-26682)\n\nIt was discovered that libass incorrectly handled certain ASS subtitle\nfiles when measuring wrapped lines. An attacker could use this issue to\ncause libass to crash, resulting in a denial of service, or possibly\nexecute arbitrary code. This issue only affected Ubuntu 24.04 LTS and\nUbuntu 26.04 LTS. (CVE-2026-61627)\n\nIt was discovered that libass incorrectly handled certain Matroska\nsubtitle chunks with negative ReadOrder values. An attacker could use\nthis issue to cause libass to crash, resulting in a denial of service,\nor possibly execute arbitrary code. This issue only affected Ubuntu\n26.04 LTS. (CVE-2026-61626)","modified":"2026-09-25T00:43:12.488757575Z","published":"2026-09-24T14:57:46Z","related":["UBUNTU-CVE-2020-24994","UBUNTU-CVE-2020-26682","UBUNTU-CVE-2026-61626","UBUNTU-CVE-2026-61627"],"upstream":["CVE-2020-24994","CVE-2020-26682","CVE-2026-61626","CVE-2026-61627","UBUNTU-CVE-2020-24994","UBUNTU-CVE-2020-26682","UBUNTU-CVE-2026-61626","UBUNTU-CVE-2026-61627"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8815-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-24994"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-26682"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-61626"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-61627"}],"affected":[{"package":{"name":"libass","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/libass?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.10.1-3ubuntu1+esm2"}]}],"versions":["0.10.1-1ubuntu1","0.10.1-3","0.10.1-3ubuntu1","0.10.1-3ubuntu1+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libass4","binary_version":"0.10.1-3ubuntu1+esm2"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2020-24994","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"score":"medium","type":"Ubuntu"}]}],"ecosystem":"Ubuntu:Pro:14.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8815-1.json"}},{"package":{"name":"libass","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/libass?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:0.14.0-1ubuntu0.1~esm1"}]}],"versions":["1:0.13.7-2","1:0.14.0-1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro","binaries":[{"binary_name":"libass9","binary_version":"1:0.14.0-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8815-1.json","cves_map":{"ecosystem":"Ubuntu:Pro:18.04:LTS","cves":[{"id":"CVE-2020-24994","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2020-26682","severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"type":"Ubuntu","score":"medium"}]}]}}},{"package":{"name":"libass","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/libass?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:0.14.0-2ubuntu0.1~esm1"}]}],"versions":["1:0.14.0-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libass9","binary_version":"1:0.14.0-2ubuntu0.1~esm1"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2020-24994","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2020-26682","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}],"ecosystem":"Ubuntu:Pro:20.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8815-1.json"}},{"package":{"name":"libass","ecosystem":"Ubuntu:Pro:24.04:LTS","purl":"pkg:deb/ubuntu/libass?arch=source&distro=esm-apps%2Fnoble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:0.17.1-2ubuntu0.1~esm1"}]}],"versions":["1:0.17.1-1","1:0.17.1-2","1:0.17.1-2build1"],"ecosystem_specific":{"binaries":[{"binary_name":"libass9","binary_version":"1:0.17.1-2ubuntu0.1~esm1"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:Pro:24.04:LTS","cves":[{"severity":[{"score":"medium","type":"Ubuntu"}],"id":"CVE-2026-61627"}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8815-1.json"}},{"package":{"name":"libass","ecosystem":"Ubuntu:Pro:26.04:LTS","purl":"pkg:deb/ubuntu/libass?arch=source&distro=esm-apps%2Fresolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:0.17.4-2ubuntu0.1~esm1"}]}],"versions":["1:0.17.3-1","1:0.17.4-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libass9","binary_version":"1:0.17.4-2ubuntu0.1~esm1"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8815-1.json","cves_map":{"cves":[{"severity":[{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-61626"},{"severity":[{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-61627"}],"ecosystem":"Ubuntu:Pro:26.04:LTS"}}}],"schema_version":"1.9.0"}