CVE-2002-20001

high

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.

References

https://www.suse.com/support/kb/doc/?id=000020510

https://www.reddit.com/r/netsec/comments/qdoosy/server_overload_by_enforcing_dhe_key_exchange/

https://www.openssl.org/blog/blog/2022/10/21/tls-groups-configuration/

https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2022-004.txt

https://support.f5.com/csp/article/K83120834

https://ieeexplore.ieee.org/document/10374117

https://gitlab.com/dheatattack/dheater

https://github.com/mozilla/ssl-config-generator/issues/162

https://github.com/Balasys/dheater

https://dheatattack.gitlab.io/

https://dheatattack.com

https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf

Details

Source: Mitre, NVD

Published: 2021-11-11

Updated: 2024-04-23

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Severity: Medium

CVSS v3

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High