Vulnerability Description
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 Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Diffie-Hellman Key Exchange Project | Diffie-Hellman Key Exchange | - |
Related Weaknesses (CWE)
References
- https://dheatattack.gitlab.io/
- https://gist.github.com/c0r0n3r/9455ddcab985c50fd1912eabf26e058bThird Party Advisory
- https://github.com/mozilla/ssl-config-generator/issues/162Issue TrackingThird Party Advisory
- https://ieeexplore.ieee.org/document/10374117
- https://link.springer.com/content/pdf/10.1007/3-540-68339-9_29.pdfTechnical DescriptionThird Party Advisory
- https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-57pt1r5.pdfTechnical DescriptionThird Party AdvisoryUS Government Resource
- https://raw.githubusercontent.com/CVEProject/cvelist/9d7fbbcabd3f44cfedc9e880775
- https://www.researchgate.net/profile/Anton-Stiglic-2/publication/2401745_SecuritTechnical DescriptionThird Party Advisory
- 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
- https://dheatattack.gitlab.io/
- https://gist.github.com/c0r0n3r/9455ddcab985c50fd1912eabf26e058bThird Party Advisory
- https://github.com/mozilla/ssl-config-generator/issues/162Issue TrackingThird Party Advisory
FAQ
What is CVE-2022-40735?
CVE-2022-40735 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 "(appr...
How severe is CVE-2022-40735?
CVE-2022-40735 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2022-40735?
Check the references section above for vendor advisories and patch information. Affected products include: Diffie-Hellman Key Exchange Project Diffie-Hellman Key Exchange.