CVE-2026-59646: DTLS handshake reassembler allocates buffer from unchecked 24-bit length

Published Aug 3, 2026
·
Updated

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).

Affected Software

3 affected components
Bouncy Castle Bouncy Castle for Java<1.85
Bouncy Castle for Java LTS<2.73.12
Bouncy Castle for Java FIPS (BC-FJA)<1.0.24, <2.0.24, <2.1.24

Event History

Aug 3, 2026
CVE Published
via MITRE·12:48 AM
Data Sourced
via MITRE·12:48 AM
DescriptionWeakness
Data Sourced
via NVD·01:16 AM
DescriptionSeverityWeakness
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2026-59646?

The severity of CVE-2026-59646 is rated at 55, indicating a moderate risk.

2

How do I fix CVE-2026-59646?

To fix CVE-2026-59646, upgrade to Bouncy Castle for Java version 1.85 or later, or corresponding LTS and FIPS versions.

3

Which versions are affected by CVE-2026-59646?

CVE-2026-59646 affects Bouncy Castle for Java before version 1.85 and LTS versions before 2.73.12.

4

What types of applications are impacted by CVE-2026-59646?

Applications using Bouncy Castle for Java for DTLS handshake processing are impacted by CVE-2026-59646.

5

Is CVE-2026-59646 a known vulnerability in Bouncy Castle FIPS?

Yes, CVE-2026-59646 also affects Bouncy Castle for Java FIPS versions before bctls-fips 1.0.24, 2.0.24, and 2.1.24.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203