CVE-2026-59650

CriticalCVSS 9.3

Published: 03/08/2026(UTC)Updated: 04/08/2026(UTC)Translated: 03/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.26%

18th percentile - higher than 18% of all known CVEs

Summary

In Bouncy Castle for Java before 1.85, the MTI/A0 Diffie-Hellman key agreement exponentiates an unvalidated peer value. This issue also affects LTS before 2.73.12.

Risk Assessment

An attacker can supply a crafted public value, potentially leading to a weak or predictable session key, enabling a man-in-the-middle attack.

Recommendation

Upgrade Bouncy Castle to version 1.85 or later (for the regular version) and to 2.73.12 or later (for LTS).

Original NVD description (English source)

In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle for Java LTS before 2.73.12.