CVE-2021-43572

Public Exploit

Description

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.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.24%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory nccgroup.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://research.nccgroup.com/2021/11/08/technical-advisory-arbitrary-signature-forgery-in-stark-bank-ecdsa-libraries/ third party advisory exploit
https://github.com/starkbank/ecdsa-python/releases/tag/v2.0.1 third party advisory release notes
https://github.com/starkbank/ecdsa-python/commit/d136170666e9510eb63c2572551805807bd4c17f third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-43572?
CVE-2021-43572 has been scored as a critical severity vulnerability.
How to fix CVE-2021-43572?
To fix CVE-2021-43572, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43572 being actively exploited in the wild?
It is possible that CVE-2021-43572 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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