CVE-2020-14966
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.13%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 1.13% probability · 66th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-347
- Affected
- kjur/jsrsasign · netapp/max data
- Source
- cve@mitre.org
EPSS 1.1% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/kjur/jsrsasign/issues/437Exploit, Issue Tracking, Third Party Advisory
- https://github.com/kjur/jsrsasign/releases/tag/8.0.17Release Notes, Third Party Advisory
- https://github.com/kjur/jsrsasign/releases/tag/8.0.18Release Notes, Third Party Advisory
- https://kjur.github.io/jsrsasign/Release Notes, Third Party Advisory
- https://security.netapp.com/advisory/ntap-20200724-0001/Third Party Advisory
- https://www.npmjs.com/package/jsrsasignProduct, Third Party Advisory
- https://github.com/kjur/jsrsasign/issues/437Exploit, Issue Tracking, Third Party Advisory
- https://github.com/kjur/jsrsasign/releases/tag/8.0.17Release Notes, Third Party Advisory
- https://github.com/kjur/jsrsasign/releases/tag/8.0.18Release Notes, Third Party Advisory
- https://kjur.github.io/jsrsasign/Release Notes, Third Party Advisory
- https://security.netapp.com/advisory/ntap-20200724-0001/Third Party Advisory
- https://www.npmjs.com/package/jsrsasignProduct, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.