Threat Intelligence Database

The sm-crypto JavaScript library for Chinese cryptographic algorithms SM2, SM3, and SM4 has a critical vulnerability in versions prior to 0.5.0. The default key generation in Node.js uses a cryptographically weak pseudo-random number generator seeded from Math.random() and the current time, allowing attackers who can observe Math.random() outputs and estimate key generation time to recover private keys and forge signatures. This issue is fixed in version 0.5.0.

The npm package sm-crypto version 0.4.0 and earlier generates SM2 private keys and signing ephemeral scalars using a predictable random number generator in Node.js environments. The library relies on jsbn's SecureRandom, which attempts to seed from window.crypto.getRandomValues in browsers but falls back to non-cryptographic sources (Math.random and wall clock time) in Node.js because window is undefined. This fallback results in keys and ephemeral values that are predictable by attackers who can observe some outputs of Math.random and estimate the generation time. This vulnerability affects the default key generation path without requiring special configuration.

CVE-2026-23966 is a critical vulnerability in the sm-crypto JavaScript library, which implements Chinese cryptographic algorithms SM2, SM3, and SM4. The flaw exists in the SM2 decryption logic prior to version 0.3.14, allowing an attacker to recover the private key by interacting with the decryption interface multiple times, typically within several hundred interactions. This vulnerability does not require authentication or user interaction and can be exploited remotely over the network. The impact includes full compromise of confidentiality and integrity of cryptographic operations relying on the affected private keys. The issue has been patched in version 0.3.14. European organizations using sm-crypto in their applications, especially those handling sensitive data or relying on SM2 for secure communications, are at risk.

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CVE-2026-23965 is a high-severity vulnerability in the sm-crypto JavaScript library implementing Chinese cryptographic algorithms SM2, SM3, and SM4. The flaw lies in the SM2 signature verification logic prior to version 0.4.0, allowing attackers to forge valid signatures for arbitrary public keys without authentication or user interaction. This signature forgery can be exploited when the message space has sufficient redundancy, enabling attackers to craft messages with fixed prefixes that satisfy verification requirements. The vulnerability impacts the integrity of cryptographic operations, potentially allowing unauthorized actions or data tampering. No known exploits are currently reported in the wild. The issue is patched in sm-crypto version 0.4.0.

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CVE-2026-23967 is a high-severity vulnerability in the sm-crypto JavaScript library implementing Chinese cryptographic algorithms SM2, SM3, and SM4. The flaw lies in the SM2 signature verification logic prior to version 0.3.14, allowing an attacker to create a new valid signature from an existing one due to signature malleability. This vulnerability does not impact confidentiality or availability but compromises signature integrity, enabling potential forgery of signed messages without requiring authentication or user interaction. No known exploits are currently reported in the wild. The issue is patched in version 0.3.14. European organizations using sm-crypto in applications that rely on SM2 signatures should urgently update to the fixed version to prevent signature forgery risks.

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