{"id":"CVE-2026-55653","summary":"Openssh: double free in red hat enterprise linux versions of openssh dh-gex client path during fips known-group validation leads to client-side denial of service","details":"A flaw was found in OpenSSH. A malicious SSH server can exploit a double free vulnerability in the Diffie-Hellman Group Exchange (DH-GEX) client path. This occurs during FIPS (Federal Information Processing Standards) mode known-group validation when the client processes attacker-controlled DH-GEX group parameters. Successful exploitation leads to client-side process termination, resulting in a Denial of Service (DoS).","modified":"2026-10-16T03:00:03.377708618Z","published":"2026-06-23T03:36:22.741Z","related":["ALSA-2026:47755","ALSA-2026:47756","ALSA-2026:47757"],"database_specific":{"unresolved_ranges":[{"extracted_events":[{"range":[{"fixed":"0:9.9p1-25.el10_2"},{"fixed":"0:9.9p1-7.el10_0.5"},{"fixed":"0:8.0p1-30.el8_10"},{"fixed":"0:8.0p1-30.el8_10"},{"fixed":"0:9.9p1-9.el9_8"},{"fixed":"0:9.9p1-9.el9_8"},{"fixed":"0:8.7p1-38.el9_4.10"},{"fixed":"0:8.7p1-45.el9_6.5"},{"fixed":"10.3p1-6.hum1"},{"fixed":"1791818590"},{"fixed":"1791818589"},{"fixed":"1791818505"},{"fixed":"1791818496"},{"fixed":"1791818502"},{"fixed":"1791818602"},{"fixed":"1791818598"},{"fixed":"1791818512"},{"fixed":"1791818587"},{"fixed":"1791818778"},{"fixed":"1791818512"},{"fixed":"1791818782"},{"fixed":"1791818782"},{"fixed":"1791818627"},{"fixed":"1791818790"},{"fixed":"1791818874"},{"fixed":"1791818792"},{"fixed":"1791818662"},{"fixed":"1791818877"},{"fixed":"1791883722"},{"fixed":"1791881612"},{"fixed":"1791885618"},{"fixed":"1791881487"},{"fixed":"1791881732"},{"fixed":"1791883315"},{"fixed":"1791881486"},{"fixed":"1791881769"},{"fixed":"1791885505"},{"fixed":"1791819252"},{"fixed":"1791818749"},{"fixed":"1791819206"},{"fixed":"1791818979"},{"fixed":"1791819123"},{"fixed":"1791818901"},{"fixed":"1791820333"},{"fixed":"1791819495"},{"fixed":"1791819104"},{"fixed":"1786435483"},{"fixed":"1786533529"},{"fixed":"1787135742"},{"fixed":"1787241260"}],"source":"AFFECTED_FIELD","strategy":"InverseAffectedRanges"}]}],"cna_assigner":"redhat","cwe_ids":["CWE-415"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55653.json"},"references":[{"type":"WEB","url":"https://access.redhat.com/downloads/content/package-browser/"},{"type":"WEB","url":"https://catalog.redhat.com/software/containers/"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:36759"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:47755"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:47756"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:47757"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:54387"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:58981"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:76748"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:76993"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:80513"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82749"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82750"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82751"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82752"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82753"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82754"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82755"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82756"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82757"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82758"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82759"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82761"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82762"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82763"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82897"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82898"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82899"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82900"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82901"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82902"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82903"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82904"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82907"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82908"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82909"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82910"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82912"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82913"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82914"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82915"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82916"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:82917"},{"type":"ADVI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