VulnerabilityAnalyzed

CVE-2026-23967

A signature malleability vulnerability exists in the SM2 signature verification logic of the sm-crypto library prior to version 0.3.14.

HIGH 7.5EPSS 0.20%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.20%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

sm-crypto provides JavaScript implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. A signature malleability vulnerability exists in the SM2 signature verification logic of the sm-crypto library prior to version 0.3.14. An attacker can derive a new valid signature for a previously signed message from an existing signature. Version 0.3.14 patches the issue.

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: 0.20% probability · 10th percentile
CISA KEV: Not listed
Weakness: CWE-347
Affected: juneandgreen/sm-crypto
Source: security-advisories@github.com

References

https://github.com/JuneAndGreen/sm-crypto/security/advisories/GHSA-qv7w-v773-3xqmVendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.