CVE-2026-73567: Juneandgreen Sm-Crypto

Critical severity, CVSS 9.1. EPSS: 0.4% chance of exploitation in the next 30 days.

sm-crypto provides JavaScript implementations of the Chinese cryptographic algorithms SM2, SM3, and SM4. Prior to 0.5.0, the default no-argument sm2.generateKeyPairHex() path in Node.js uses the module-wide SecureRandom instance in src/sm2/utils.js, supplied by jsbn@1.1.0, which seeds an ARC4 stream from Math.random() and new Date().getTime() because window.crypto.getRandomValues is unavailable even though globalThis.crypto exists. An attacker who can observe the process's Math.random() outputs and estimate the key-generation time can reconstruct the seed, recover generated SM2 private keys, and predict signing ephemeral scalars used to forge signatures. This issue is fixed in version 0.5.0.

Affected products

• Juneandgreen Sm-Crypto: before 0.5.0 (fixed in 0.5.0)

Published 2026-08-13. Last modified 2026-09-18.