CVE-2002-20001
HIGH severity · CVSS 7.5 · Uncontrolled resource consumption
7.5CVSS HIGH
Summary
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.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactNone
Integrity impactNone
Availability impactHigh
Exploit probability (EPSS)25%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products we track (3)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdfAdvisory
- https://dheatattack.comAdvisory
- https://dheatattack.gitlab.io/Advisory
- https://github.com/Balasys/dheaterAdvisory
- https://github.com/mozilla/ssl-config-generator/issues/162
- https://gitlab.com/dheatattack/dheaterAdvisory
- https://ieeexplore.ieee.org/document/10374117Advisory
- https://support.f5.com/csp/article/K83120834Advisory