CVE-2026-59646CWE-789

CVE-2026-59646

High · published August 3, 2026

CVSS v3.1

7.5

EPSS

Percentile

48.9

In the wild

Unconfirmed

What it is

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).

The record

Technical detail

CVSS v3.1: 7.5 · HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0: Not supplied
EPSS: 0.00616 · 48.9th percentile
Weakness: CWE-789 · Memory Allocation with Excessive Size Value
Published: 2026-08-03T05:16Z

Affected products (5)

Product	Versions	Fixed in
bouncycastle/bc-java	< 1.85	1.85
bouncycastle/bctls-fips	< 1.0.24	1.0.24
bouncycastle/bctls-fips	≥ 2.0.19, < 2.0.24	2.0.24
bouncycastle/bctls-fips	≥ 2.1.20, < 2.1.24	2.1.24
bouncycastle/bouncy_castle_for_java_lts	≤ 2.73.11	—

References (3)

https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa · 91579145-5d7b-4cc5-b925-a0262ff19630 https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9 · 91579145-5d7b-4cc5-b925-a0262ff19630 https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059646 · 91579145-5d7b-4cc5-b925-a0262ff19630

EPSS history

Timeline

03 AUG 00:48Z
DTLS handshake reassembler allocates buffer from unchecked 24-bit length
cvelistv5