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
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 Vector Breakdown
AV:NAttack VectorAC:LAttack ComplexityPR:NPrivileges RequiredUI:RUser InteractionS:UScopeC:NConfidentialityI:NIntegrityA:LAvailabilityWeaknesses
Affected Products
Attack Graph
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Exploitability
MITRE ATT&CK
1 techniqueReferences
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