{"id":"UBUNTU-CVE-2016-4956","details":"ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (interleaved-mode transition and time change) via a spoofed broadcast packet.  NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-1548.","modified":"2026-02-04T03:51:42.324793Z","published":"2016-07-04T00:00:00Z","related":["USN-3096-1"],"upstream":["CVE-2016-4956"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2016-4956"},{"type":"REPORT","url":"http://support.ntp.org/bin/view/Main/SecurityNotice#June_2016_ntp_4_2_8p8_NTP_Securi"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-3096-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2016-4956"}],"affected":[{"package":{"name":"ntp","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/ntp@1:4.2.6.p5+dfsg-3ubuntu2.14.04.10?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:4.2.6.p5+dfsg-3ubuntu2.14.04.10"}]}],"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","1:4.2.6.p5+dfsg-3ubuntu2.14.04.3","1:4.2.6.p5+dfsg-3ubuntu2.14.04.5","1:4.2.6.p5+dfsg-3ubuntu2.14.04.6","1:4.2.6.p5+dfsg-3ubuntu2.14.04.7","1:4.2.6.p5+dfsg-3ubuntu2.14.04.8"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_version":"1:4.2.6.p5+dfsg-3ubuntu2.14.04.10","binary_name":"ntp"},{"binary_version":"1:4.2.6.p5+dfsg-3ubuntu2.14.04.10","binary_name":"ntpdate"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2016/UBUNTU-CVE-2016-4956.json"}},{"package":{"name":"ntp","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/ntp@1:4.2.8p4+dfsg-3ubuntu5.3?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:4.2.8p4+dfsg-3ubuntu5.3"}]}],"versions":["1:4.2.6.p5+dfsg-3ubuntu8","1:4.2.6.p5+dfsg-3ubuntu8.1","1:4.2.6.p5+dfsg-3ubuntu9","1:4.2.8p4+dfsg-3ubuntu1","1:4.2.8p4+dfsg-3ubuntu2","1:4.2.8p4+dfsg-3ubuntu3","1:4.2.8p4+dfsg-3ubuntu4","1:4.2.8p4+dfsg-3ubuntu5","1:4.2.8p4+dfsg-3ubuntu5.1","1:4.2.8p4+dfsg-3ubuntu5.2"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_version":"1:4.2.8p4+dfsg-3ubuntu5.3","binary_name":"ntp"},{"binary_version":"1:4.2.8p4+dfsg-3ubuntu5.3","binary_name":"ntpdate"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2016/UBUNTU-CVE-2016-4956.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L"},{"type":"Ubuntu","score":"low"}]}