CVE DATABASE / CVE-2022-40735
CVE-2022-40735
Summary
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.
CVSS 3.1 breakdown
| 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 |
| Attack vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity | NONE |
| Availability | HIGH |
Weakness type (CWE)
Affected products
Use our free CVE Lookup tool for the latest NVD record, or browse the full CISA KEV catalog.
References
- https://dheatattack.gitlab.io/
- https://gist.github.com/c0r0n3r/9455ddcab985c50fd1912eabf26e058b
- https://github.com/mozilla/ssl-config-generator/issues/162
- https://ieeexplore.ieee.org/document/10374117
- https://link.springer.com/content/pdf/10.1007/3-540-68339-9_29.pdf
- https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-57pt1r5.pdf
- https://raw.githubusercontent.com/CVEProject/cvelist/9d7fbbcabd3f44cfedc9e8807757d31ece85a2c6/2022/40xxx/CVE-2022-40735.json
- https://www.researchgate.net/profile/Anton-Stiglic-2/publication/2401745_Security_Issues_in_the_Diffie-Hellman_Key_Agreement_Protocol/links/546c144f0cf20dedafd53e7e/Security-Issues-in-the-Diffie-Hellman-Key-Agreement-Protocol.pdf
- https://www.rfc-editor.org/rfc/rfc3526
- https://www.rfc-editor.org/rfc/rfc4419
- https://www.rfc-editor.org/rfc/rfc5114#section-4
- https://www.rfc-editor.org/rfc/rfc7919#section-5.2
Data: NIST NVD. NVD last modified 2024-11-21. Always verify against the vendor advisory before acting.