CVE Catalog

CVE-2002-20001

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Very high risk
24.64%

98th percentile - higher than 98% of all known CVEs

Summary

The Diffie-Hellman Key Agreement Protocol allows remote attackers (client-side) to send arbitrary numbers that are not public keys, triggering expensive server-side DHE modular-exponentiation calculations, known as D(HE)at attack. The client needs minimal CPU and bandwidth. The attack may be more disruptive if the client can force the server to use its largest key size.

Risk Assessment

The D(HE)at attack can cause denial of service by overloading the server with expensive computations, potentially disrupting service availability.

Recommendation

Configure the server to restrict DHE usage, enforce key size limits, and implement protections against resource exhaustion.

Related vulnerabilities

Original NVD description (English source)

The Diffie-Hellman Key Agreement Protocol allows remote attackers (from the client side) to send arbitrary numbers that are actually not public keys, and trigger expensive server-side DHE modular-exponentiation calculations, aka a D(HE)at or D(HE)ater attack. The client needs very little CPU resources and network bandwidth. The attack may be more disruptive in cases where a client can require a server to select its largest supported key size. The basic attack scenario is that the client must claim that it can only communicate with DHE, and the server must be configured to allow DHE.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS