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).
CVSS breakdown
CVSS 3.1
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Affected products
- OpenBSD / OpenSSH
- RedHat / enterprise_linux10.0 – 10.0
- RedHat / enterprise_linux8.0 – 8.0
- RedHat / enterprise_linux9.0 – 9.0
- RedHat / enterprise_linux6.0 – 6.0
- RedHat / enterprise_linux7.0 – 7.0
- RedHat / hardened_images
- RedHat / openshift_container_platform4.0 – 4.0
References
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:36759
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:47755
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:47756
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:47757
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:54387
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:58981
- VENDOR_ADVISORYhttps://access.redhat.com/security/cve/CVE-2026-55653
- MISChttps://bugzilla.redhat.com/show_bug.cgi?id=2462351
Updated 16m ago · 8 sources