CVE-2026-55653

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).

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:36759
https://access.redhat.com/errata/RHSA-2026:47755
https://access.redhat.com/errata/RHSA-2026:47756
https://access.redhat.com/errata/RHSA-2026:47757
https://access.redhat.com/errata/RHSA-2026:54387
https://access.redhat.com/errata/RHSA-2026:58981
https://access.redhat.com/security/cve/CVE-2026-55653	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2462351	Exploit Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	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:::::::*

History

No history.

Information

Published : 2026-06-23 04:17

Updated : 2026-09-01 13:19

NVD link : CVE-2026-55653

Mitre link : CVE-2026-55653

CVE.ORG link : CVE-2026-55653

JSON object : View

Products Affected

redhat

enterprise_linux
openshift_container_platform
hardened_images

openbsd

openssh

CWE

CWE-415

Double Free

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