CVE-2026-4258
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 0.2%
exploitation probability
0.2%top 84% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
References
https://gist.github.com/Kr0emer/2560f98edb10b0b34f2438cd63913c47https://github.com/bitwiseshiftleft/sjcl/blob/master/core/ecc.js%23L454-L461https://github.com/bitwiseshiftleft/sjcl/commit/ee307459972442a17beebc29dc331fffd8aff796https://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-15751243https://security.snyk.io/vuln/SNYK-JS-SJCL-15369617