Vulnerability · Published Mar 17, 2026 · Assigned by snyk

CVE-2026-4258

High 7.5

In plain English

A high-severity security flaw in org.webjars.npm:sjcl. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.3%top 82.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	sjcl	1.0.9	GHSA-2w8x-224x-785m

Affected products (as reported)

Vendor	Product	Versions
n/a	sjcl	0 – before 1.0.9
n/a	org.webjars.npm:sjcl	0 – before *

Weakness: CWE-347, CWE-325 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:P

In plain English

Official description

Affected packages & fixed versions

Affected products (as reported)

References