cve.bz

CVE-2021-43572

9.8 criticalEPSS 1.2%

Critical (9.8) in starkbank ecdsa-python. EPSS 1.2% chance of exploitation in the next 30 days. Fixed in starkbank-ecdsa 2.0.1.

The verify function in the Stark Bank Python ECDSA library (aka starkbank-escada or ecdsa-python) before 2.0.1 fails to check that the signature is non-zero, which allows attackers to forge signatures on arbitrary messages.

Severity

CVSS 3.1

9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.2% chance of exploitation in the next 30 days; higher than 69% of CVEs (scores of 2026-10-31)
CWE
CWE-347
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-92vm-mxjf-jqf3PyPIstarkbank-ecdsa<2.0.12.0.1
PYSEC-2021-426PyPIstarkbank-ecdsa<2.0.12.0.1

References

Check your stackJSON