CVE-2026-59644 PUBLISHED

MLS hash-ratchet honours arbitrary 32-bit generation counter from sender

Assigner: bcorg
Reserved: 06.07.2026 Published: 03.08.2026 Updated: 03.08.2026

In Bouncy Castle for Java before 1.85, MLS hash-ratchet honours arbitrary 32-bit generation counter from sender.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/U:Amber
CVSS Score: 8.7

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Vendor	Legion of the Bouncy Castle Inc.
Product	BC-JAVA
Versions	Default: unaffected affected from 1.73 to 1.85 (excl.)