{"id":"UBUNTU-CVE-2020-21547","details":"Libsixel 1.8.2 contains a heap-based buffer overflow in the dither_func_fs function in tosixel.c.","modified":"2026-04-22T12:33:40.425162Z","published":"2021-09-17T21:15:00Z","upstream":["CVE-2020-21547"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-21547"},{"type":"REPORT","url":"https://github.com/saitoha/libsixel/issues/114"},{"type":"REPORT","url":"https://github.com/saitoha/libsixel/commit/9d0a7ff417b66d80a4bff714de1f27b24742f55a"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2020-21547"}],"affected":[{"package":{"name":"libsixel","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/libsixel@1.5.2-2?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.2-1","1.5.2-2"],"ecosystem_specific":{"binaries":[{"binary_version":"1.5.2-2","binary_name":"libsixel-bin"},{"binary_name":"libsixel1","binary_version":"1.5.2-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-21547.json"}},{"package":{"name":"libsixel","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/libsixel@1.7.3-1?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.5.2-2","1.7.3-1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.7.3-1","binary_name":"libsixel-bin"},{"binary_name":"libsixel-examples","binary_version":"1.7.3-1"},{"binary_name":"libsixel1","binary_version":"1.7.3-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-21547.json"}},{"package":{"name":"libsixel","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/libsixel@1.8.2-2.1?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.2-1","1.8.2-2.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libsixel-bin","binary_version":"1.8.2-2.1"},{"binary_name":"libsixel-examples","binary_version":"1.8.2-2.1"},{"binary_name":"libsixel1","binary_version":"1.8.2-2.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-21547.json"}}],"schema_version":"1.7.5","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"}]}