Resource exhaustion in Diffie-Hellman Key Exchange Project
CVE-2022-40735
The Diffie-Hellman Key Agreement Protocol allows use of long exponents that arguably make certain calculations unnecessarily expensive, because the 1996 van Oorschot and Wiener paper found that "(appropriately) short exponents" can be used when there are adequate subgroup constraints, and these short exponents can lead to less expensive calculations than for long exponents. This issue is different from CVE-2002-20001 because it is based on an observation about exponent size, rather than an observation about numbers that are not public keys. The specific situations in which calculation expense would constitute a server-side vulnerability depend on the protocol (e.g., TLS, SSH, or IKE) and the DHE implementation details. In general, there might be an availability concern because of server-side resource consumption from DHE modular-exponentiation calculations. Finally, it is possible for an attacker to exploit this vulnerability and CVE-2002-20001 together.
Vulnerability class: DoS (Denial of Service)
EPSS: 0.023 (81.5th percentile) — read the EPSS interpretation.
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.
Affected products
- Diffie-hellman_key_exchange_project Diffie-hellman_key_exchange
- N/a — versions n/a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (Third Party Advisory, Issue Tracking)
- cve@mitre.org (Third Party Advisory)
- cve@mitre.org (Technical Description, Third Party Advisory)
- cve@mitre.org (Technical Description, Third Party Advisory)
- cve@mitre.org (Technical Description, US Government Resource, Third Party Advisory)
- cve@mitre.org
- cve@mitre.org
- cve@mitre.org
- cve@mitre.org
- cve@mitre.org
Frequently asked questions
- What is CVE-2022-40735?
- CVE-2022-40735 is a high-severity vulnerability in Diffie-Hellman Key Exchange Project, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2022-11-14.
- How severe is CVE-2022-40735?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2022-40735 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.