Balasys Dheater
CVE-2002-20001
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.
What this means for your business
- It affects Balasys Dheater. It matters if your company, or a supplier that handles your data, runs it.
- Code showing how to exploit it has been published, but real attacks have not been confirmed.
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 25% chance of attack attempts being seen in the next 30 days, ranking above 97% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Balasys Dheater, and which version. The affected versions are listed further down this page.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Fastnexa security experts
Not sure if your company is exposed to CVE-2002-20001?
Tell us where you run Balasys Dheater and a Fastnexa penetration tester will check whether this flaw, or others like it, can be used against your websites, apps and network.
The full test is free for our first 10 founding clients until 31 December 2026. See the offer
Think you’ve already been hit? Don’t wait on a form: call or WhatsApp +1 (732) 454 2616. We reply within 1 hour, 24/7. Emergency help →
Scoring
- CVSS
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness
- CWE-400
- Assigned by
- cve@mitre.org
Dates
- Published
- 2021-11-11
- Last modified
- 2026-09-23
- Sources
- NVD
Affected products
- Balasys Dheaterall versions
- Siemens Scalance W1750d Firmwareall versions
- Siemens Scalance W1750dall versions
- Suse Linux Enterprise Server11, 12, 15
- F5 Big-Ip Access Policy Manager13.1.0 - 16.1.4, 17.0.0 - 17.1.0
- F5 Big-Ip Advanced Firewall Manager13.1.0 - 17.1.2, 17.5.0
- F5 Big-Ip Advanced Web Application Firewall13.1.0 - 17.1.2, 17.5.0
- F5 Big-Ip Analytics13.1.0 - 17.1.2, 17.5.0
- F5 Big-Ip Application Acceleration Manager13.1.0 - 17.1.2, 17.5.0
- F5 Big-Ip Application Security Manager13.1.0 - 17.1.2, 17.5.0
- F5 Big-Ip Application Visibility And Reporting13.1.0 - 17.1.2, 17.5.0
- F5 Big-Ip Carrier-Grade Nat13.1.0 - 17.1.2, 17.5.0
As listed in the NVD configuration data. Not a statement about your estate.
References
- https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf
- https://dheatattack.com/
- https://dheatattack.gitlab.io/
- https://github.com/Balasys/dheater
- https://github.com/mozilla/ssl-config-generator/issues/162
- https://gitlab.com/dheatattack/dheater
- https://ieeexplore.ieee.org/document/10374117
- https://support.f5.com/csp/article/K83120834
- https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2022-004.txt
- https://www.openssl.org/blog/blog/2022/10/21/tls-groups-configuration/
- https://www.reddit.com/r/netsec/comments/qdoosy/server_overload_by_enforcing_dhe_key_exchange/
- https://www.researchgate.net/profile/Anton-Stiglic-2/publication/2401745_Security_Issues_in_the_Diffie-Hellman_Key_Agreement_Protocol
- https://www.suse.com/support/kb/doc/?id=000020510
- https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf
- https://dheatattack.com/