CVE-2026-4599

The functions getRandomBigIntegerZeroToMax and getRandomBigIntegerMinToMax in the file src/crypto-1.1.js use incorrect compareTo method checks that accept candidates outside the allowed range. This causes systematic bias in the random nonces used during DSA signature generation. An attacker, by observing a sufficient number of signatures, can statistically extract the pattern resulting from this bias and perform a cryptographic attack allowing recovery of the private key.

An attacker can recover the private DSA key used to generate digital signatures, leading to complete takeover of the victim's cryptographic identity — including the ability to forge signatures and impersonate the key owner.

The jsrsasign package should be updated to version 11.1.1 or later, which fixes the incorrect compareTo checks. The patch is available in commit ee4b013478366cb16cea9a4bdfb218b6077f83b1 in the project repository on GitHub.

The jsrsasign package (Jsrsasign Project) in versions from 7.0.0 (inclusive) to 11.1.1 (exclusive) that utilize DSA signature functionality.