id: PYSEC-2021-426
details: The verify function in the Stark Bank Python ECDSA library (ecdsa-python)
  2.0.0 fails to check that the signature is non-zero, which allows attackers to forge
  signatures on arbitrary messages.
affected:
- package:
    name: starkbank-ecdsa
    ecosystem: PyPI
    purl: pkg:pypi/starkbank-ecdsa
  ranges:
  - type: ECOSYSTEM
    events:
    - introduced: '0'
    - fixed: 2.0.1
  versions:
  - '0.1'
  - 0.1.1
  - 0.1.2
  - 0.1.3
  - 0.1.4
  - 0.1.5
  - 0.1.6
  - 0.1.7
  - 0.1.8
  - 0.1.9
  - 1.0.0
  - 1.1.0
  - 1.1.1
  - 2.0.0
references:
- type: ADVISORY
  url: https://research.nccgroup.com/2021/11/08/technical-advisory-arbitrary-signature-forgery-in-stark-bank-ecdsa-libraries/
- type: WEB
  url: https://github.com/starkbank/ecdsa-python/releases/tag/v2.0.1
- type: ADVISORY
  url: https://github.com/advisories/GHSA-92vm-mxjf-jqf3
aliases:
- CVE-2021-43572
- GHSA-92vm-mxjf-jqf3
modified: '2021-11-16T03:58:45.828098Z'
published: '2021-11-09T22:15:00Z'