{"id":"CVE-2015-7871","url":"https://www.cyber-defence.io/tools/cve/CVE-2015-7871","generatedAt":"2026-11-05T04:33:55.183Z","title":"Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authentication.","description":"Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authentication.","published":"2017-08-07T20:29:01.000Z","lastModified":"2026-06-17T00:33:18.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-287"],"affected":["ntp/ntp","debian/debian linux","netapp/oncommand balance","netapp/oncommand performance manager","netapp/oncommand unified manager","netapp/clustered data ontap","netapp/data ontap"],"epss":{"score":0.81762,"percentile":0.99646,"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 81.8%, higher than 100% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://support.ntp.org/bin/view/Main/NtpBug2941","tags":["Vendor Advisory"],"source":"cve@mitre.org"},{"url":"http://www.debian.org/security/2015/dsa-3388","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://www.securityfocus.com/bid/77287","tags":["Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"http://www.securitytracker.com/id/1033951","tags":["Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1274265","tags":["Issue Tracking","Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdf","source":"cve@mitre.org"},{"url":"https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05270839","tags":["Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/201604-03","tags":["Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/201607-15","tags":["Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20171004-0001/","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://support.ntp.org/bin/view/Main/NtpBug2941","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.debian.org/security/2015/dsa-3388","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securityfocus.com/bid/77287","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id/1033951","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1274265","tags":["Issue Tracking","Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdf","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05270839","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/201604-03","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/201607-15","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20171004-0001/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2015-7871","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."}