{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-26466","assignerOrgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","state":"PUBLISHED","assignerShortName":"redhat","dateReserved":"2025-02-10T18:31:47.979Z","datePublished":"2025-02-28T21:25:28.861Z","dateUpdated":"2026-02-10T17:13:57.386Z"},"containers":{"cna":{"title":"Openssh: denial-of-service in openssh","metrics":[{"other":{"content":{"value":"Moderate","namespace":"https://access.redhat.com/security/updates/classification/"},"type":"Red Hat severity rating"}},{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":5.9,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"format":"CVSS"}],"descriptions":[{"lang":"en","value":"A flaw was found in the OpenSSH package. For each ping packet the SSH server receives, a pong packet is allocated in a memory buffer and stored in a queue of packages. It is only freed when the server/client key exchange has finished. A malicious client may keep sending such packages, leading to an uncontrolled increase in memory consumption on the server side. Consequently, the server may become unavailable, resulting in a denial of service attack."}],"affected":[{"repo":"https://anongit.mindrot.org/openssh.git","versions":[{"status":"affected","version":"9.5p1","versionType":"custom","lessThanOrEqual":"9.9p1"}],"packageName":"OpenSSH","collectionURL":"https://www.openssh.com/","defaultStatus":"unaffected"},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openssh","defaultStatus":"unaffected","cpes":["cpe:/o:redhat:enterprise_linux:10"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openssh","defaultStatus":"unaffected","cpes":["cpe:/o:redhat:enterprise_linux:6"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openssh","defaultStatus":"unaffected","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 8","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openssh","defaultStatus":"unaffected","cpes":["cpe:/o:redhat:enterprise_linux:8"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openssh","defaultStatus":"unaffected","cpes":["cpe:/o:redhat:enterprise_linux:9"]},{"vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 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/etc/ssh/sshd_config\n\nMaxStartups: Set to a reasonable value, this option controls the maximum number of concurrent unauthenticated connections the SSH server accepts;\n\nPerSourcePenalties: Set its suboptions to a reasonable value, this option is used to help sshd to detect and drop connections that are potentially malicious for the SSH server;\n\nLoginGraceTime: Set to a resonable value, this option controls how much time the SSH server will wait the client to authenticate before dropping its connection;\n\nAll the three option above needs to be set to implement a full mitigation for this vulnerability."}],"timeline":[{"lang":"en","time":"2025-02-11T19:51:30.375Z","value":"Reported to Red Hat."},{"lang":"en","time":"2025-02-18T00:00:00.000Z","value":"Made 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