{"id":"UBUNTU-CVE-2021-4011","details":"A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SwapCreateRegister function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.","modified":"2026-04-22T12:59:58.742653Z","published":"2021-12-14T12:00:00Z","related":["USN-5193-1","USN-5193-2","USN-5193-3"],"upstream":["CVE-2021-4011"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-4011"},{"type":"REPORT","url":"https://www.openwall.com/lists/oss-security/2021/12/14/1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5193-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5193-2"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5193-3"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-4011"}],"affected":[{"package":{"name":"xorg-server","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/xorg-server@2:1.15.1-0ubuntu2.11+esm5?arch=source&distro=trusty/esm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2:1.15.1-0ubuntu2.11+esm5"}]}],"versions":["2:1.14.3-3ubuntu2","2:1.14.3-3ubuntu3","2:1.14.3-3ubuntu4","2:1.14.3-5ubuntu1","2:1.14.4-1ubuntu1","2:1.14.4-1ubuntu2","2:1.14.4.901-0ubuntu2","2:1.14.5-1ubuntu2","2:1.14.5-1ubuntu4","2:1.15.0-1ubuntu1","2:1.15.0-1ubuntu2","2:1.15.0-1ubuntu3","2:1.15.0-1ubuntu4","2:1.15.0-1ubuntu6","2:1.15.0-1ubuntu7","2:1.15.1-0ubuntu1","2:1.15.1-0ubuntu2","2:1.15.1-0ubuntu2.1","2:1.15.1-0ubuntu2.4","2:1.15.1-0ubuntu2.5","2:1.15.1-0ubuntu2.6","2:1.15.1-0ubuntu2.7","2:1.15.1-0ubuntu2.9","2:1.15.1-0ubuntu2.10","2:1.15.1-0ubuntu2.11","2:1.15.1-0ubuntu2.11+esm2","2:1.15.1-0ubuntu2.11+esm3","2:1.15.1-0ubuntu2.11+esm4"],"ecosystem_specific":{"availability":"Available 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