Resource exhaustion in 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.
Vulnerability class: DoS (Denial of Service)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.246 (97.9th percentile), scored .
Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 98th percentile — 97.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.246 · newest: 0.246 · change: 0.000
Affected products
- Balasys Dheater
- F5 Big-Ip Access Policy Manager
- F5 Big-Ip Advanced Firewall Manager — versions 17.5.0
- F5 Big-Ip Advanced Web Application Firewall — versions 17.5.0
- F5 Big-Ip Analytics — versions 17.5.0
- F5 Big-Ip Application Acceleration Manager — versions 17.5.0
- F5 Big-Ip Application Security Manager — versions 17.5.0
- F5 Big-Ip Application Visibility And Reporting — versions 17.5.0
- F5 Big-Ip Carrier-Grade Nat — versions 17.5.0
- F5 Big-Ip Ddos Hybrid Defender — versions 17.5.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/Balasys/dheater (Product, Third Party Advisory)
- www.researchgate.net/profile/Anton-Stiglic-2/publication/2401745_Security_Issue… (Technical Description, Exploit)
- www.reddit.com/r/netsec/comments/qdoosy/server_overload_by_enforcing_dhe_key_ex… (Issue Tracking)
- github.com/mozilla/ssl-config-generator/issues/162 (Issue Tracking)
- cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf (Third Party Advisory)
- www.suse.com/support/kb/doc/ (Third Party Advisory)
- www.openssl.org/blog/blog/2022/10/21/tls-groups-configuration/ (Third Party Advisory)
- www.arubanetworks.com/assets/alert/ARUBA-PSA-2022-004.txt (Technical Description, Third Party Advisory)
- support.f5.com/csp/article/K83120834 (Third Party Advisory)
- dheatattack.com (Third Party Advisory)
Frequently asked questions
- What is CVE-2002-20001?
- CVE-2002-20001 is a high-severity vulnerability in Balasys Dheater, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2021-11-11.
- How severe is CVE-2002-20001?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2002-20001 known to be exploited?
- 14 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.