{"id":"CVE-2016-9566","url":"https://www.cyber-defence.io/tools/cve/CVE-2016-9566","generatedAt":"2026-10-28T21:16:11.884Z","title":"base/logging.c in Nagios Core before 4.2.4 allows local users with access to an account in the nagios group to gain root privileges via a symlink attack on the log file.","description":"base/logging.c in Nagios Core before 4.2.4 allows local users with access to an account in the nagios group to gain root privileges via a symlink attack on the log file.  NOTE: this can be leveraged by remote attackers using CVE-2016-9565.","published":"2016-12-15T22:59:01.000Z","lastModified":"2026-06-17T00:56:15.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":7.8,"severity":"HIGH","vector":"CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-59","CWE-264"],"affected":["nagios/nagios"],"epss":{"score":0.04885,"percentile":0.92023,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":1,"verified":true,"firstPublished":"2016-12-15","source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[{"edbId":40921,"kind":"exploit","title":"Nagios < 4.2.4 - Local Privilege Escalation","url":"https://www.exploit-db.com/exploits/40921","sourceUrl":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/linux/local/40921.sh","file":"exploits/linux/local/40921.sh","published":"2016-12-15","added":"2016-12-15","updated":"2016-12-16","author":"Dawid Golunski","type":"local","platform":"linux","port":null,"verified":true,"codes":["CVE-2016-9566"],"tags":"Local","aliases":null,"applicationUrl":"http://www.exploit-db.comnagios-4.2.1.tar.gz","screenshotUrl":null,"referenceUrl":"https://legalhackers.com/advisories/Nagios-Exploit-Root-PrivEsc-CVE-2016-9566.html"}]},"verdict":{"level":"urgent","text":"A public exploit is published in Exploit-DB (verified) and the impact is high, while EPSS rates exploitation at 4.9%. Anyone can run this; patch or mitigate before the next change window and check exposed instances for signs of use."},"changes":[],"references":[{"url":"http://rhn.redhat.com/errata/RHSA-2017-0211.html","source":"cve@mitre.org"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0212.html","source":"cve@mitre.org"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0213.html","source":"cve@mitre.org"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0214.html","source":"cve@mitre.org"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0258.html","source":"cve@mitre.org"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0259.html","source":"cve@mitre.org"},{"url":"http://seclists.org/fulldisclosure/2016/Dec/58","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://www.securityfocus.com/bid/94919","tags":["Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"http://www.securitytracker.com/id/1037487","source":"cve@mitre.org"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1402869","tags":["Issue Tracking"],"source":"cve@mitre.org"},{"url":"https://github.com/NagiosEnterprises/nagioscore/commit/c29557dec91eba2306f5fb11b8da4474ba63f8c4","tags":["Issue Tracking","Patch"],"source":"cve@mitre.org"},{"url":"https://legalhackers.com/advisories/Nagios-Exploit-Root-PrivEsc-CVE-2016-9566.html","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2018/12/msg00014.html","source":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/201612-51","source":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/201702-26","source":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/201710-20","source":"cve@mitre.org"},{"url":"https://www.exploit-db.com/exploits/40921/","source":"cve@mitre.org"},{"url":"https://www.nagios.org/projects/nagios-core/history/4x/","tags":["Vendor Advisory"],"source":"cve@mitre.org"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0211.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0212.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0213.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0214.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0258.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2017-0259.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://seclists.org/fulldisclosure/2016/Dec/58","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securityfocus.com/bid/94919","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id/1037487","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1402869","tags":["Issue Tracking"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/NagiosEnterprises/nagioscore/commit/c29557dec91eba2306f5fb11b8da4474ba63f8c4","tags":["Issue Tracking","Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://legalhackers.com/advisories/Nagios-Exploit-Root-PrivEsc-CVE-2016-9566.html","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2018/12/msg00014.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/201612-51","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/201702-26","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/201710-20","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.exploit-db.com/exploits/40921/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.nagios.org/projects/nagios-core/history/4x/","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2016-9566","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."}