{"id":"USN-4966-1","summary":"libx11 vulnerability","details":"It was discovered that libx11 incorrectly validated certain parameter\nlengths. A remote attacker could possibly use this issue to trick libx11\ninto emitting extra X protocol requests.\n","modified":"2026-02-10T04:42:12Z","published":"2021-05-25T17:00:37Z","related":["UBUNTU-CVE-2021-31535"],"upstream":["CVE-2021-31535","UBUNTU-CVE-2021-31535"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4966-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-31535"}],"affected":[{"package":{"name":"libx11","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/libx11@2:1.6.4-3ubuntu0.4?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:1.6.4-3ubuntu0.4"}]}],"versions":["2:1.6.4-3","2:1.6.4-3ubuntu0.1","2:1.6.4-3ubuntu0.2","2:1.6.4-3ubuntu0.3"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libx11-6","binary_version":"2:1.6.4-3ubuntu0.4"},{"binary_name":"libx11-data","binary_version":"2:1.6.4-3ubuntu0.4"},{"binary_name":"libx11-dev","binary_version":"2:1.6.4-3ubuntu0.4"},{"binary_name":"libx11-xcb-dev","binary_version":"2:1.6.4-3ubuntu0.4"},{"binary_name":"libx11-xcb1","binary_version":"2:1.6.4-3ubuntu0.4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4966-1.json","cves_map":{"ecosystem":"Ubuntu:18.04:LTS","cves":[{"id":"CVE-2021-31535","severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"score":"medium","type":"Ubuntu"}]}]}}},{"package":{"name":"libx11","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/libx11@2:1.6.9-2ubuntu1.2?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:1.6.9-2ubuntu1.2"}]}],"versions":["2:1.6.8-1","2:1.6.9-2","2:1.6.9-2ubuntu1","2:1.6.9-2ubuntu1.1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libx11-6","binary_version":"2:1.6.9-2ubuntu1.2"},{"binary_name":"libx11-data","binary_version":"2:1.6.9-2ubuntu1.2"},{"binary_name":"libx11-dev","binary_version":"2:1.6.9-2ubuntu1.2"},{"binary_name":"libx11-xcb-dev","binary_version":"2:1.6.9-2ubuntu1.2"},{"binary_name":"libx11-xcb1","binary_version":"2:1.6.9-2ubuntu1.2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4966-1.json","cves_map":{"ecosystem":"Ubuntu:20.04:LTS","cves":[{"id":"CVE-2021-31535","severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"score":"medium","type":"Ubuntu"}]}]}}}],"schema_version":"1.7.3"}