CVE-2026-55653

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

MEDIUM 4.3

En bref

Source: NVD
EPSS: EPSS 0.53 % · centile 45 (2026-10-28)
État: PUBLISHED
Publiée: 2026-06-23 03:36 UTC
Mise à jour: 2026-10-26 03:26 UTC
Attribuée par: redhat
Statut NVD: Modified

Description

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).

Faiblesses (CWE)

CWE-415 — Double libération

Références

Scores

Version	Score	Vecteur	Évalué par
CVSS 3.1	MEDIUM 4.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L	redhat
CVSS 3.1	MEDIUM 4.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L	NVD · secalert@redhat.com (Secondary)
CVSS 3.1	MEDIUM 6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H	NVD · nvd@nist.gov (Primary)

Références européennes

ENISA EUVD · EUVD-2026-38412
GCVE · GCVE-0-2026-55653

Avis du CERT-FR

CERTFR-2026-AVI-1094 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Configurations affectées (CPE NVD)

cpe:2.3:a:openbsd:openssh:-:*:*:*:*:*:*:*
cpe:2.3:a:redhat:hardened_images:-:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*

Produits affectés

Produit	Versions
Red Hat · Red Hat Enterprise Linux 10	unaffected 0:9.9p1-25.el10_2 < *
Red Hat · Red Hat Enterprise Linux 10.0 Extended Update Support	unaffected 0:9.9p1-7.el10_0.5 < *
Red Hat · Red Hat Enterprise Linux 8	unaffected 0:8.0p1-30.el8_10 < *
Red Hat · Red Hat Enterprise Linux 8	unaffected 0:8.0p1-30.el8_10 < *
Red Hat · Red Hat Enterprise Linux 9	unaffected 0:9.9p1-9.el9_8 < *
Red Hat · Red Hat Enterprise Linux 9	unaffected 0:9.9p1-9.el9_8 < *
Red Hat · Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions	unaffected 0:8.7p1-30.el9_2.13 < *
Red Hat · Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions	unaffected 0:8.7p1-38.el9_4.10 < *
Red Hat · Red Hat Enterprise Linux 9.6 Extended Update Support	unaffected 0:8.7p1-45.el9_6.5 < *
Red Hat · Red Hat Hardened Images	unaffected 10.3p1-6.hum1 < *
Red Hat · Red Hat OpenShift AI 3.0	unaffected 1791818590 < *
Red Hat · Red Hat OpenShift AI 3.0	unaffected 1791818589 < *
Red Hat · Red Hat OpenShift AI 3.0	unaffected 1791818505 < *
Red Hat · Red Hat OpenShift AI 3.0	unaffected 1791818496 < *
Red Hat · Red Hat OpenShift AI 3.0	unaffected 1791818502 < *
Red Hat · Red Hat OpenShift AI 3.2	unaffected 1791818602 < *
Red Hat · Red Hat OpenShift AI 3.2	unaffected 1791818598 < *
Red Hat · Red Hat OpenShift AI 3.2	unaffected 1791818512 < *
Red Hat · Red Hat OpenShift AI 3.2	unaffected 1791818587 < *
Red Hat · Red Hat OpenShift AI 3.2	unaffected 1791818778 < *

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD