---
id: CVE-2026-59646
title: >-
  In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates
  buffer from unchecked 24-bit length
summary: >-
  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-fip…
severity: none
cwe:
  - CWE-789
published: '2026-08-03'
updated: '2026-08-03'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-59646'
references:
  - url: >-
      https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa
    label: 91579145-5d7b-4cc5-b925-a0262ff19630
  - url: >-
      https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9
    label: 91579145-5d7b-4cc5-b925-a0262ff19630
  - url: 'https://github.com/bcgit/bc-java/wiki/CVE-2026-59646'
    label: 91579145-5d7b-4cc5-b925-a0262ff19630
tags:
  - nvd
ingestedAt: '2026-08-03T01:21:07.929Z'
epss: 0.00353
epssPercentile: 0.29072
---

## Overview

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).

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.