{"id":"CVE-2016-4953","url":"https://www.cyber-defence.io/tools/cve/CVE-2016-4953","generatedAt":"2026-11-05T05:27:51.014Z","title":"ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (ephemeral-association demobilization) by sending a spoofed crypto-NAK packet with incorrect authentication data at a certain time.","description":"ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (ephemeral-association demobilization) by sending a spoofed crypto-NAK packet with incorrect authentication data at a certain time.","published":"2016-07-05T01:59:00.000Z","lastModified":"2026-06-17T00:48:29.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-287"],"affected":["ntp/ntp","oracle/solaris","suse/manager","suse/manager proxy","suse/openstack cloud","opensuse/leap","opensuse/opensuse","suse/linux enterprise desktop","suse/linux enterprise server","siemens/simatic net cp 443-1 opc ua firmware","siemens/tim 4r-ie firmware","siemens/tim 4r-ie dnp3 firmware"],"epss":{"score":0.17245,"percentile":0.97111,"date":"2026-11-04","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 17.2%, higher than 97% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://bugs.ntp.org/3045","tags":["Issue Tracking","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00018.html","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00020.html","source":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00023.html","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00024.html","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00028.html","tags":["Mailing List","Third Party 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Advisory"],"source":"cve@mitre.org"},{"url":"http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160603-ntpd","source":"cve@mitre.org"},{"url":"http://www.kb.cert.org/vuls/id/321640","tags":["Third Party Advisory","US Government Resource"],"source":"cve@mitre.org"},{"url":"http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html","tags":["Third Party 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Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2016-4953","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}