Is CVE-2026-59649 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-59649 being exploited in the wild.

How severe is CVE-2026-59649?

High severity, with a CVSS score of 7.5, published 3 August 2026.

Is there a fix for CVE-2026-59649?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-59649 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-59649?

Check whether you run Bouncy Castle for Java at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-59649: Bouncy Castle OpenPGP denial of service via unbounded subpacket length

CVE-2026-59649 · Severity: high · CVSS 7.5 · Published 2026-08-03

Bouncy Castle is a widely-used cryptography library that provides OpenPGP support for secure communications. A flaw in OpenPGP user-attribute subpacket handling allows an attacker to craft malicious PGP messages that consume unlimited memory on the processing system, potentially causing application crashes or denial of service.

Technologies: Bouncy Castle for Java. Vendors: Bouncy Castle.

Quick answers

Is CVE-2026-59649 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-59649 being exploited in the wild.
How severe is CVE-2026-59649?: High severity, with a CVSS score of 7.5, published 3 August 2026.
Which products and versions are affected?: Bouncy Castle for Java before 1.85.
Is there a fix for CVE-2026-59649?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-59649 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-59649?: Check whether you run Bouncy Castle for Java at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability is a denial-of-service flaw in Bouncy Castle's OpenPGP implementation. The user-attribute subpacket length is bounded only by the JVM's maximum available memory, allowing an attacker to send a specially crafted OpenPGP message with an extremely large subpacket length value. This causes the library to attempt to allocate excessive memory when parsing the malformed packet, leading to out-of-memory errors and application termination. No authentication is required; the attack vector is network-based and exploitable by any user who can send PGP data to an affected application. The vulnerability affects Bouncy Castle for Java before 1.85, Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bcpg-fips 1.0.13, 2.0.13, and 2.1.13 respectively.

Affected products

Bouncy Castle Bouncy Castle for Java before 1.85
Bouncy Castle Bouncy Castle for Java LTS before 2.73.12
Bouncy Castle Bouncy Castle for Java FIPS (bcpg-fips) before 1.0.13 (1.0.X), before 2.0.13 (2.0.X), before 2.1.13 (2.1.X)

Timeline

2026-08-03: disclosed: CVE-2026-59649 published

References

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