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).
Severity (CVSS)
| Base score | 4.3 |
|---|---|
| Severity | Medium |
| Version | CVSS 3.1 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L |
| Provided by | CNA |
Weaknesses
- CWE-415 — Double Free
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 6 | — |
| Red Hat | Red Hat Enterprise Linux 7 | — |
| Red Hat | Red Hat Enterprise Linux 8 | — |
| Red Hat | Red Hat Enterprise Linux 9 | — |
| Red Hat | Red Hat Hardened Images | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — |
References
- https://access.redhat.com/security/cve/CVE-2026-55653 (vdb-entry x_refsource_REDHAT)
- https://bugzilla.redhat.com/show_bug.cgi?id=2462351 (issue-tracking x_refsource_REDHAT)
Generated from the official CVE List on 23 Jun 2026 10:05 UTC.