CVE-2026-42767

A flaw was found in OpenSSL. An attacker controlling a Certificate Management Protocol (CMP) server, or acting as a man-in-the-middle, could craft a malicious CMP response. This response, containing a Certificate Request Message Format (CRMF) CertRepMessage with a specific malformed EncryptedValue structure, would trigger a NULL pointer dereference in the OpenSSL CMP client. This vulnerability leads to a crash of the application, resulting in a Denial of Service (DoS).

This is a Low severity issue. A null pointer dereference flaw in the OpenSSL Certificate Management Protocol (CMP) client could be triggered by an attacker-controlled CMP server. This could lead to a denial of service in applications that process untrusted CMP/CRMF messages.

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.

To mitigate this issue, ensure that OpenSSL CMP client applications only communicate with trusted Certificate Management Protocol (CMP) servers. If CMP client functionality is not required, consider disabling or restricting its use to reduce exposure.