Depending on the details of the DHE implementation, the strength of the server might be reduced due to the use of short exponents. This weakness might be exploited by an active adversary with significant resources, who could attempt to downgrade the security of a trusted server. This server-side weakness might be exploited by an active adversary with significant resources, who could attempt to downgrade the security of a trusted server.

Weaknesses in the Server-Side Implementation

The weakness in the server-side implementation of DHE is that it allows an active adversary with significant resources to attempt to downgrade the security of a trusted server. This vulnerability has been known since at least 2007 and has been fixed by NIST in its SP 800-56A Rev. 1 standards for TLS implementations.

Overview of DHE-Based Exchange Server Weakness

The DHE-based Exchange Server implementation suffers from a server-side weakness, which could be exploited by an active adversary with significant resources.

CVE-2023-40736

Depending on the details of the DHE implementation, the strength of the server might be reduced due to the use of short exponents. This weakness might be exploited by an active adversary with significant resources, who could attempt to downgrade the security of a trusted server.
The following ANSI X9.31-compliant cryptographic algorithms are vulnerable to this issue: RSA, Diffie-Hellman, and DSA.

Timeline

Published on: 11/14/2022 23:15:00 UTC
Last modified on: 11/21/2022 22:15:00 UTC

References