CVE-2026-59646

In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates buffer from unchecked 24-bit length. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bctls-fips 1.0.24 (1.0.X series), 2.0.24 (2.0.X series) and 2.1.24 (2.1.X series).

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa	Patch
https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9	Patch
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059646	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:bouncycastle:bc-java::::::::
	cpe:2.3:a:bouncycastle:bctls-fips::::::::
	cpe:2.3:a:bouncycastle:bctls-fips::::::::
	cpe:2.3:a:bouncycastle:bctls-fips::::::::
	cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts::::::::

History

No history.

Information

Published : 2026-08-03 01:16

Updated : 2026-08-28 19:57

NVD link : CVE-2026-59646

Mitre link : CVE-2026-59646

CVE.ORG link : CVE-2026-59646

JSON object : View

Products Affected

bouncycastle

bouncy_castle_for_java_lts
bc-java
bctls-fips

CWE

CWE-789

Memory Allocation with Excessive Size Value

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