{"id":"USN-8991-1","summary":"rxvt-unicode vulnerability","details":"It was discovered that rxvt-unicode incorrectly handled certain escape\nsequences. An attacker could possibly use this issue to execute arbitrary\ncode if a user displayed specially crafted text in the terminal.","modified":"2026-11-04T03:43:14.812270901Z","published":"2026-11-03T17:37:49Z","related":["UBUNTU-CVE-2021-33477"],"upstream":["CVE-2021-33477","UBUNTU-CVE-2021-33477"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8991-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-33477"}],"affected":[{"package":{"name":"rxvt-unicode","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/rxvt-unicode?arch=source&distro=esm-apps-legacy%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.21-1ubuntu0.1~esm1"}]}],"versions":["9.21-1","9.21-1build1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro","binaries":[{"binary_version":"9.21-1ubuntu0.1~esm1","binary_name":"rxvt-unicode"},{"binary_name":"rxvt-unicode-256color","binary_version":"9.21-1ubuntu0.1~esm1"},{"binary_name":"rxvt-unicode-lite","binary_version":"9.21-1ubuntu0.1~esm1"},{"binary_version":"9.21-1ubuntu0.1~esm1","binary_name":"rxvt-unicode-ml"}]},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2021-33477","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},{"score":"medium","type":"Ubuntu"}]}],"ecosystem":"Ubuntu:Pro:16.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8991-1.json"}},{"package":{"name":"rxvt-unicode","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/rxvt-unicode?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.22-3ubuntu0.1~esm1"}]}],"versions":["9.22-1build2","9.22-3"],"ecosystem_specific":{"binaries":[{"binary_name":"aterm","binary_version":"9.22-3ubuntu0.1~esm1"},{"binary_version":"9.22-3ubuntu0.1~esm1","binary_name":"aterm-ml"},{"binary_version":"1:2.7.10-7.1+urxvt9.22-3ubuntu0.1~esm1","binary_name":"rxvt"},{"binary_version":"1:2.7.10-7.1+urxvt9.22-3ubuntu0.1~esm1","binary_name":"rxvt-ml"},{"binary_name":"rxvt-unicode","binary_version":"9.22-3ubuntu0.1~esm1"},{"binary_version":"9.22-3ubuntu0.1~esm1","binary_name":"rxvt-unicode-256color"},{"binary_name":"rxvt-unicode-lite","binary_version":"9.22-3ubuntu0.1~esm1"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2021-33477","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}],"ecosystem":"Ubuntu:Pro:18.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8991-1.json"}},{"package":{"name":"rxvt-unicode","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/rxvt-unicode?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.22-6ubuntu0.1~esm1"}]}],"versions":["9.22-6build1","9.22-6build2","9.22-6build3"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro","binaries":[{"binary_name":"aterm","binary_version":"9.22-6ubuntu0.1~esm1"},{"binary_name":"aterm-ml","binary_version":"9.22-6ubuntu0.1~esm1"},{"binary_version":"1:2.7.10-7.1+urxvt9.22-6ubuntu0.1~esm1","binary_name":"rxvt"},{"binary_name":"rxvt-ml","binary_version":"1:2.7.10-7.1+urxvt9.22-6ubuntu0.1~esm1"},{"binary_name":"rxvt-unicode","binary_version":"9.22-6ubuntu0.1~esm1"},{"binary_version":"9.22-6ubuntu0.1~esm1","binary_name":"rxvt-unicode-256color"},{"binary_name":"rxvt-unicode-lite","binary_version":"9.22-6ubuntu0.1~esm1"}]},"database_specific":{"cves_map":{"cves":[{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2021-33477"}],"ecosystem":"Ubuntu:Pro:20.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8991-1.json"}}],"schema_version":"1.9.2"}