# CVE-2002-20001

## Summary

- **CVE ID:** CVE-2002-20001
- **Severity:** UNKNOWN
- **CVSS Score:** 0.73
- **CWE:** N/A
- **Published:** Nov 11, 2021
- **Last Modified:** Mar 16, 2026

## Description

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.

## Affected Products

- n/a — n/a (n/a)

## References

- [CNA](https://github.com/Balasys/dheater)
- [CNA](https://www.researchgate.net/profile/Anton-Stiglic-2/publication/2401745_Security_Issues_in_the_Diffie-Hellman_Key_Agreement_Protocol)
- [CNA](https://www.reddit.com/r/netsec/comments/qdoosy/server_overload_by_enforcing_dhe_key_exchange/)
- [CNA](https://github.com/mozilla/ssl-config-generator/issues/162)
- [CNA](https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf)
- [CNA](https://www.suse.com/support/kb/doc/?id=000020510)
- [CNA](https://www.openssl.org/blog/blog/2022/10/21/tls-groups-configuration/)
- [CNA](https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2022-004.txt)
- [CNA](https://support.f5.com/csp/article/K83120834)
- [CNA](https://dheatattack.com)
- [CNA](https://gitlab.com/dheatattack/dheater)
- [CNA](https://dheatattack.gitlab.io/)
- [CNA](https://ieeexplore.ieee.org/document/10374117)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 14.68%
- **EPSS Percentile:** 94.3

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._