CVE Catalog

CVE-2026-4258

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.25%

16th percentile - higher than 16% of all known CVEs

Summary

The sjcl library before version 1.0.9 lacks point-on-curve validation in sjcl.ecc.basicKey.publicKey(). An attacker can recover a victim's ECDH private key by sending crafted off-curve public keys and observing ECDH outputs. The dhJavaEc() function returns the raw x-coordinate without hashing, providing a plaintext oracle.

Risk Assessment

An attacker can recover the victim's ECDH private key, allowing decryption of communications and impersonation, compromising confidentiality and authenticity.

Recommendation

Upgrade the sjcl library to version 1.0.9 or later, which includes point-on-curve validation.

Related vulnerabilities

Original NVD description (English source)

Versions of the package sjcl before 1.0.9 are vulnerable to Improper Verification of Cryptographic Signature due to missing point-on-curve validation in sjcl.ecc.basicKey.publicKey(). An attacker can recover a victim's ECDH private key by sending crafted off-curve public keys and observing ECDH outputs. The dhJavaEc() function directly returns the raw x-coordinate of the scalar multiplication result (no hashing), providing a plaintext oracle without requiring any decryption feedback.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS