{"id":"CVE-2016-2181","url":"https://www.cyber-defence.io/tools/cve/CVE-2016-2181","generatedAt":"2026-11-05T05:14:48.079Z","title":"The Anti-Replay feature in the DTLS implementation in OpenSSL before 1.1.0 mishandles early use of a new epoch number in conjunction with a large sequence number, which allows remote attackers to cause a denial of service (false-positive packet drops)…","description":"The Anti-Replay feature in the DTLS implementation in OpenSSL before 1.1.0 mishandles early use of a new epoch number in conjunction with a large sequence number, which allows remote attackers to cause a denial of service (false-positive packet drops) via spoofed DTLS records, related to rec_layer_d1.c and ssl3_record.c.","published":"2016-09-16T05:59:01.000Z","lastModified":"2026-06-17T00:43:36.000Z","status":"Modified","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"3.0","score":7.5,"severity":"HIGH","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-189"],"affected":["openssl/openssl","oracle/linux"],"epss":{"score":0.22634,"percentile":0.97729,"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 22.6%, higher than 98% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00022.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00023.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00024.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00031.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00005.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00011.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00012.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00029.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2017-10/msg00010.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2017-10/msg00011.html","source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2018-02/msg00032.html","source":"secalert@redhat.com"},{"url":"http://rhn.redhat.com/errata/RHSA-2016-1940.html","source":"secalert@redhat.com"},{"url":"http://seclists.org/fulldisclosure/2017/Jul/31","source":"secalert@redhat.com"},{"url":"http://www-01.ibm.com/support/docview.wss?uid=swg21995039","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://www.debian.org/security/2016/dsa-3673","source":"secalert@redhat.com"},{"url":"http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20170322-01-openssl-en","source":"secalert@redhat.com"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpuapr2018-3678067.html","source":"secalert@redhat.com"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html","source":"secalert@redhat.com"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html","source":"secalert@redhat.com"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html","source":"secalert@redhat.com"},{"url":"http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2016-3090545.html","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://www.oracle.com/technetwork/topics/security/ovmbulletinoct2016-3090547.html","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://www.securityfocus.com/bid/92982","tags":["Third Party Advisory","VDB Entry"],"source":"secalert@redhat.com"},{"url":"http://www.securitytracker.com/id/1036690","source":"secalert@redhat.com"},{"url":"http://www.splunk.com/view/SP-CAAAPSV","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://www.splunk.com/view/SP-CAAAPUE","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://www.ubuntu.com/usn/USN-3087-1","source":"secalert@redhat.com"},{"url":"http://www.ubuntu.com/usn/USN-3087-2","source":"secalert@redhat.com"},{"url":"https://bto.bluecoat.com/security-advisory/sa132","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf","source":"secalert@redhat.com"},{"url":"https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=1fb9fdc3027b27d8eb6a1e6a846435b070980770","source":"secalert@redhat.com"},{"url":"https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA40312","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://kc.mcafee.com/corporate/index?page=content&id=SB10215","source":"secalert@redhat.com"},{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-16:26.openssl.asc","source":"secalert@redhat.com"},{"url":"https://support.f5.com/csp/article/K59298921","source":"secalert@redhat.com"},{"url":"https://www.arista.com/en/support/advisories-notices/security-advisories/1749-security-advisory-24","source":"secalert@redhat.com"},{"url":"https://www.tenable.com/security/tns-2016-16","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.tenable.com/security/tns-2016-20","source":"secalert@redhat.com"},{"url":"https://www.tenable.com/security/tns-2016-21","source":"secalert@redhat.com"},{"url":"http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00022.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00023.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00024.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00031.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00005.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00011.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00012.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00029.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2017-10/msg00010.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2017-10/msg00011.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2018-02/msg00032.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2016-1940.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://seclists.org/fulldisclosure/2017/Jul/31","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www-01.ibm.com/support/docview.wss?uid=swg21995039","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.debian.org/security/2016/dsa-3673","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20170322-01-openssl-en","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpuapr2018-3678067.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2016-2181","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."}