{"id":"UBUNTU-CVE-2016-2517","details":"NTP before 4.2.8p7 and 4.3.x before 4.3.92 allows remote attackers to cause a denial of service (prevent subsequent authentication) by leveraging knowledge of the controlkey or requestkey and sending a crafted packet to ntpd, which changes the value of trustedkey, controlkey, or requestkey. NOTE: this vulnerability exists because of a CVE-2016-2516 regression.","modified":"2025-10-24T04:45:39Z","published":"2017-01-30T21:59:00Z","upstream":["CVE-2016-2517"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2016-2517"},{"type":"REPORT","url":"http://support.ntp.org/bin/view/Main/SecurityNotice#April_2016_NTP_4_2_8p7_Security"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2016-2517"}],"affected":[{"package":{"name":"ntp","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/ntp@1:4.2.6.p5+dfsg-3ubuntu2.14.04.13+esm1?arch=source&distro=esm-infra-legacy/trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"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","1:4.2.6.p5+dfsg-3ubuntu2.14.04.10","1:4.2.6.p5+dfsg-3ubuntu2.14.04.11","1:4.2.6.p5+dfsg-3ubuntu2.14.04.12","1:4.2.6.p5+dfsg-3ubuntu2.14.04.13","1:4.2.6.p5+dfsg-3ubuntu2.14.04.13+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"ntp","binary_version":"1:4.2.6.p5+dfsg-3ubuntu2.14.04.13+esm1"},{"binary_name":"ntpdate","binary_version":"1:4.2.6.p5+dfsg-3ubuntu2.14.04.13+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2016/UBUNTU-CVE-2016-2517.json"}},{"package":{"name":"ntp","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/ntp@1:4.2.8p4+dfsg-3ubuntu5.10?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"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","1:4.2.8p4+dfsg-3ubuntu5.3","1:4.2.8p4+dfsg-3ubuntu5.4","1:4.2.8p4+dfsg-3ubuntu5.5","1:4.2.8p4+dfsg-3ubuntu5.6","1:4.2.8p4+dfsg-3ubuntu5.7","1:4.2.8p4+dfsg-3ubuntu5.8","1:4.2.8p4+dfsg-3ubuntu5.9","1:4.2.8p4+dfsg-3ubuntu5.10"],"ecosystem_specific":{"binaries":[{"binary_name":"ntp","binary_version":"1:4.2.8p4+dfsg-3ubuntu5.10"},{"binary_name":"ntpdate","binary_version":"1:4.2.8p4+dfsg-3ubuntu5.10"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2016/UBUNTU-CVE-2016-2517.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"negligible"}]}