CVE-2021-43569
CVSS v3
9.8
CRITICAL
EPSS Score
1.1 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
The verify function in the Stark Bank .NET ECDSA library (ecdsa-dotnet) 1.3.1 fails to check that the signature is non-zero, which allows attackers to forge signatures on arbitrary messages.
Technical details
- Published
- 2021-11-09
Frequently asked questions
What is CVE-2021-43569?
The verify function in the Stark Bank .NET ECDSA library (ecdsa-dotnet) 1.3.1 fails to check that the signature is non-zero, which allows attackers to forge signatures on arbitrary messages.
Is CVE-2021-43569 actively exploited?
Active exploitation of CVE-2021-43569 has not been confirmed. Its EPSS score was 1.1% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-43569?
CVE-2021-43569 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-43569 affecting your environment?
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