{"id":"CVE-2016-6309","url":"https://www.cyber-defence.io/tools/cve/CVE-2016-6309","generatedAt":"2026-10-27T22:05:03.645Z","title":"statem/statem.c in OpenSSL 1.1.0a does not consider memory-block movement after a realloc call, which allows remote attackers to cause a denial of service (use-after-free) or possibly execute arbitrary code via a crafted TLS session.","description":"statem/statem.c in OpenSSL 1.1.0a does not consider memory-block movement after a realloc call, which allows remote attackers to cause a denial of service (use-after-free) or possibly execute arbitrary code via a crafted TLS session.","published":"2016-09-26T19:59:06.000Z","lastModified":"2026-06-17T00:50:48.000Z","status":"Modified","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"3.0","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-416"],"affected":["openssl/openssl"],"epss":{"score":0.70223,"percentile":0.99377,"date":"2026-10-26","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 70.2%, higher than 99% 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","source":"secalert@redhat.com"},{"url":"http://www-01.ibm.com/support/docview.wss?uid=swg21995039","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","source":"secalert@redhat.com"},{"url":"http://www.securityfocus.com/bid/93177","source":"secalert@redhat.com"},{"url":"http://www.securitytracker.com/id/1036885","source":"secalert@redhat.com"},{"url":"https://bto.bluecoat.com/security-advisory/sa132","source":"secalert@redhat.com"},{"url":"https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=acacbfa7565c78d2273c0b2a2e5e803f44afefeb","source":"secalert@redhat.com"},{"url":"https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03856en_us","source":"secalert@redhat.com"},{"url":"https://www.openssl.org/news/secadv/20160926.txt","tags":["Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.tenable.com/security/tns-2016-16","source":"secalert@redhat.com"},{"url":"https://www.tenable.com/security/tns-2016-20","source":"secalert@redhat.com"},{"url":"http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www-01.ibm.com/support/docview.wss?uid=swg21995039","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"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securityfocus.com/bid/93177","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id/1036885","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bto.bluecoat.com/security-advisory/sa132","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=acacbfa7565c78d2273c0b2a2e5e803f44afefeb","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03856en_us","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.openssl.org/news/secadv/20160926.txt","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.tenable.com/security/tns-2016-16","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.tenable.com/security/tns-2016-20","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2016-6309","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."}