CVE-2026-42770

A flaw was found in OpenSSL. A malicious peer can exploit this vulnerability by presenting a specially crafted DHX (X9.42) peer key. Due to improper validation of the peer key's subgroup membership, an attacker can recover the victim's private key after a small number of key exchange attempts. This information disclosure can lead to unauthorized access or further compromise of affected systems.

This Low severity flaw in OpenSSL affects systems configured to use DHX (X9.42) peer keys for key derivation, allowing a malicious peer to potentially recover a victim's private key. The attack requires specific conditions, such as long-lived RA/CA DHX keys in CMP deployments or bespoke applications utilizing X9.42 DHX static keys with interactive protocols, limiting its broader impact.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.