{"id":"UBUNTU-CVE-2016-0772","details":"The smtplib library in CPython (aka Python) before 2.7.12, 3.x before 3.4.5, and 3.5.x before 3.5.2 does not return an error when StartTLS fails, which might allow man-in-the-middle attackers to bypass the TLS protections by leveraging a network position between the client and the registry to block the StartTLS command, aka a \"StartTLS stripping attack.\"","modified":"2026-02-04T03:31:12.779048Z","published":"2016-09-02T00:00:00Z","related":["USN-3134-1"],"upstream":["CVE-2016-0772"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2016-0772"},{"type":"REPORT","url":"http://www.openwall.com/lists/oss-security/2016/06/14/9"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-3134-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2016-0772"}],"affected":[{"package":{"name":"python2.7","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/python2.7@2.7.6-8ubuntu0.3?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.7.6-8ubuntu0.3"}]}],"versions":["2.7.5-8ubuntu3","2.7.5-8ubuntu4","2.7.6-2","2.7.6-2ubuntu1","2.7.6-3","2.7.6-3ubuntu1","2.7.6-4","2.7.6-4ubuntu1","2.7.6-5","2.7.6-7","2.7.6-8","2.7.6-8ubuntu0.2"],"ecosystem_specific":{"availability":"No subscription 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