CVE-2026-59644 - Vulnerability Details - OpenCVE

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

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Vendors	Products
Legion Of The Bouncy Castle Inc.	Bc-java

No data.

No data.

References

Link	Providers
https://github.com/bcgit/bc-java/commit/610d8757d855afe197df0de6d831cb75c81e3b9f
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059644

History

Mon, 03 Aug 2026 16:15:00 +0000

Type	Values Removed	Values Added
First Time appeared		Legion Of The Bouncy Castle Inc. Legion Of The Bouncy Castle Inc. bc-java
Vendors & Products		Legion Of The Bouncy Castle Inc. Legion Of The Bouncy Castle Inc. bc-java

Mon, 03 Aug 2026 14:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 03 Aug 2026 05:30:00 +0000

Type	Values Removed	Values Added
References	https://github.com/bcgit/bc-java/wiki/CVE-2026-59644	https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059644

Mon, 03 Aug 2026 01:15:00 +0000

Type	Values Removed	Values Added
Description		In Bouncy Castle for Java before 1.85, MLS hash-ratchet honours arbitrary 32-bit generation counter from sender.
Title		MLS hash-ratchet honours arbitrary 32-bit generation counter from sender
Weaknesses		CWE-834
References		https://github.com/bcgit/bc-java/commit/610d8757d855afe197df0de6d831cb75c81e3b9f https://github.com/bcgit/bc-java/wiki/CVE-2026-59644
Metrics		cvssV4_0 `{'score': 8.7, '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'}`

MITRE

Status: PUBLISHED

Assigner: bcorg

Published: 2026-08-03T00:50:50.154Z

Updated: 2026-08-03T13:36:10.480Z

Reserved: 2026-07-06T06:58:29.263Z

Link: CVE-2026-59644

Vulnrichment

Updated: 2026-08-03T13:36:06.556Z

NVD

No data.

Redhat

No data.

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