{"id":"UBUNTU-CVE-2015-1798","details":"The symmetric-key feature in the receive function in ntp_proto.c in ntpd in NTP 4.x before 4.2.8p2 requires a correct MAC only if the MAC field has a nonzero length, which makes it easier for man-in-the-middle attackers to spoof packets by omitting the MAC.","modified":"2026-01-30T02:13:40.118637Z","published":"2015-04-08T00:00:00Z","related":["USN-2567-1"],"upstream":["CVE-2015-1798"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2015-1798"},{"type":"REPORT","url":"http://support.ntp.org/bin/view/Main/SecurityNotice#Recent_Vulnerabilities"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-2567-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2015-1798"}],"affected":[{"package":{"name":"ntp","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/ntp@1:4.2.6.p5+dfsg-3ubuntu2.14.04.3?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:4.2.6.p5+dfsg-3ubuntu2.14.04.3"}]}],"versions":["1:4.2.6.p5+dfsg-3ubuntu2","1:4.2.6.p5+dfsg-3ubuntu2.14.04.1","1:4.2.6.p5+dfsg-3ubuntu2.14.04.2"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"ntp","binary_version":"1:4.2.6.p5+dfsg-3ubuntu2.14.04.3"},{"binary_name":"ntpdate","binary_version":"1:4.2.6.p5+dfsg-3ubuntu2.14.04.3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2015/UBUNTU-CVE-2015-1798.json"}}],"schema_version":"1.7.3","severity":[{"type":"Ubuntu","score":"medium"}]}