CVE-2026-23965: Juneandgreen Sm-Crypto

High severity, CVSS 7.5. EPSS: 0.2% chance of exploitation in the next 30 days.

sm-crypto provides JavaScript implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. A signature forgery vulnerability exists in the SM2 signature verification logic of sm-crypto prior to version 0.4.0. Under default configurations, an attacker can forge valid signatures for arbitrary public keys. If the message space contains sufficient redundancy, the attacker can fix the prefix of the message associated with the forged signature to satisfy specific formatting requirements. Version 0.4.0 patches the issue.

Affected products

• Juneandgreen Sm-Crypto: before 0.4.0 (fixed in 0.4.0)

Published 2026-01-22. Last modified 2026-06-17.