Security context
What an agent needs to avoid regressing past fixes and find the next vuln in this repo.
starkbank/ecdsa-python
master @ 6d515be
6
Fixes
1
CVEs
CRITICAL
Peak severity
Highlights
Cryptographic Issues: 2 prior fixes. Scrutinize any change in this area.
ellipticcurve/ecdsa.py: most-fixed (4 issues). Treat as high-risk during review.
4 high-severity fixes in this history; regressions here are high-impact.
Recurring patterns
The bug types that recur here, drawn from past fixes, not open vulnerabilities.
Signature Bypass: Inadequate verification allowed signature bypasses and complete forgery (as tracked in CVE-2021-43572). The verify function failed to ensure that points at infinity were rejected and that signature coordinates (r, s) were non-zero and within valid mathematical bounds.
Cryptography: The use of the cryptographically insecure 'random.randint' for nonce generation in ECDSA signatures could expose the private key to recovery attacks. Secure random generation using SystemRandom is mandatory for all secret derivations.
Signature Malleability: Signatures could be altered or appended with trailing junk data without invalidating them due to a lack of strict low-S signature normalization and weak DER-encoding format validations.