Vulnerability Description
Generating the ECDSA nonce k samples a random number r and then truncates this randomness with a modular reduction mod n where n is the order of the elliptic curve. Meaning k = r mod n. The division used during the reduction estimates a factor q_e by dividing the upper two digits (a digit having e.g. a size of 8 byte) of r by the upper digit of n and then decrements q_e in a loop until it has the correct size. Observing the number of times q_e is decremented through a control-flow revealing side-channel reveals a bias in the most significant bits of k. Depending on the curve this is either a negligible bias or a significant bias large enough to reconstruct k with lattice reduction methods. For SECP160R1, e.g., we find a bias of 15 bits.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Wolfssl | Wolfssl | < 5.7.2 |
Related Weaknesses (CWE)
References
- https://github.com/wolfSSL/wolfssl/pull/7020
- https://github.com/wolfSSL/wolfssl/releases/tag/v5.7.2-stableRelease Notes
FAQ
What is CVE-2024-1544?
CVE-2024-1544 is a vulnerability with a CVSS score of 4.1 (MEDIUM). Generating the ECDSA nonce k samples a random number r and then truncates this randomness with a modular reduction mod n where n is the order of the elliptic curve. Meaning k = r mod n. The division...
How severe is CVE-2024-1544?
CVE-2024-1544 has been rated MEDIUM with a CVSS base score of 4.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2024-1544?
Check the references section above for vendor advisories and patch information. Affected products include: Wolfssl Wolfssl.