CVE-2024-1544 ECDSA nonce bias caused by truncation
Side-channel leakage in ECDSA nonce generation allows attackers to recover private keys via lattice reduction.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-1544?
CVE-2024-1544 is a medium-severity vulnerability in Wolfssl Wolfssl, published on 27 Aug 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-203
Which versions are affected by CVE-2024-1544?
It affects 1 product.
Products include Wolfssl Wolfssl.
How do I fix CVE-2024-1544?
Apply the vendor's patch.
Is CVE-2024-1544 being exploited?
There is no known exploitation of CVE-2024-1544 in the wild and no public exploit code.
Other vulnerabilities in Wolfssl Wolfssl
Sources
Also known as DEBIAN-CVE-2024-1544, GHSA-grjj-54gm-q5vf, JLSEC-2026-682, UBUNTU-CVE-2024-1544.