CVSS v3
7.5
HIGH
EPSS Score
1.1 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
An issue was discovered in the jsrsasign package through 8.0.18 for Node.js. It allows a malleability in ECDSA signatures by not checking overflows in the length of a sequence and '0' characters appended or prepended to an integer. The modified signatures are verified as valid. This could have a security-relevant impact if an application relied on a single canonical signature.
Technical details
- Published
- 2020-06-22
Frequently asked questions
What is CVE-2020-14966?
An issue was discovered in the jsrsasign package through 8.0.18 for Node.js. It allows a malleability in ECDSA signatures by not checking overflows in the length of a sequence and '0' characters appended or prepended to an integer. The modified signatures are verified as valid. This could have a security-relevant impact if an application relied on a single canonical signature.
Is CVE-2020-14966 actively exploited?
Active exploitation of CVE-2020-14966 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-2020-14966?
CVE-2020-14966 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2020-14966 affecting your environment?
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