{"id":"CVE-2023-25136","url":"https://www.cyber-defence.io/tools/cve/CVE-2023-25136","generatedAt":"2026-11-04T23:41:05.322Z","title":"OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling.","description":"OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states \"remote code execution is theoretically possible.\"","published":"2023-02-03T06:15:09.000Z","lastModified":"2026-10-14T23:17:15.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H"},"cwe":["CWE-415"],"affected":["openbsd/openssh","fedoraproject/fedora","netapp/ontap select deploy administration utility","netapp/a250 firmware","netapp/500f firmware","netapp/c250 firmware"],"epss":{"score":0.89792,"percentile":0.9979,"date":"2026-11-03","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 89.8%, higher than 100% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://www.openwall.com/lists/oss-security/2023/02/13/1","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2023/02/22/1","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2023/02/22/2","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2023/02/23/3","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2023/03/06/1","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2023/03/09/2","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://bugzilla.mindrot.org/show_bug.cgi?id=3522","tags":["Exploit","Issue Tracking","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://ftp.openbsd.org/pub/OpenBSD/patches/7.2/common/017_sshd.patch.sig","tags":["Patch","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/openssh/openssh-portable/commit/486c4dc3b83b4b67d663fb0fa62bc24138ec3946","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://jfrog.com/blog/openssh-pre-auth-double-free-cve-2023-25136-writeup-and-proof-of-concept/","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JGAUIXJ3TEKCRKVWFQ6GDAGQFTIIGQQP/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R7LKQDFZWKYHQ65TBSH2X2HJQ4V2THS3/","source":"cve@mitre.org"},{"url":"https://news.ycombinator.com/item?id=34711565","tags":["Issue Tracking","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/202307-01","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20230309-0003/","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://www.openwall.com/lists/oss-security/2023/02/02/2","tags":["Exploit","Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2023/02/13/1","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2023/02/22/1","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2023/02/22/2","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2023/02/23/3","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2023/03/06/1","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2023/03/09/2","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.mindrot.org/show_bug.cgi?id=3522","tags":["Exploit","Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://ftp.openbsd.org/pub/OpenBSD/patches/7.2/common/017_sshd.patch.sig","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/openssh/openssh-portable/commit/486c4dc3b83b4b67d663fb0fa62bc24138ec3946","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://jfrog.com/blog/openssh-pre-auth-double-free-cve-2023-25136-writeup-and-proof-of-concept/","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JGAUIXJ3TEKCRKVWFQ6GDAGQFTIIGQQP/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R7LKQDFZWKYHQ65TBSH2X2HJQ4V2THS3/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://news.ycombinator.com/item?id=34711565","tags":["Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202307-01","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20230309-0003/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.openwall.com/lists/oss-security/2023/02/02/2","tags":["Exploit","Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","source":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-25136","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."}