# CVE-2026-59645: Bouncy Castle for Java OER parser unbounded recursion in IEEE 1609.2 schema

Source: https://junglewise.ai/threats/cve-2026-59645-bouncy-castle-for-java-oer-parser-unbounded-recursion-in-ieee  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-03. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-59645 · Severity: high · CVSS 7.5 · Published 2026-08-03

Bouncy Castle for Java is a widely-used cryptographic library that processes digital certificates and protocol messages for security applications. An attacker can craft a malicious message using the IEEE 1609.2 schema format that causes the OER parser to recurse indefinitely, exhausting memory and crashing the application, resulting in a denial-of-service attack against any service using this library.

Technologies: [Bouncy Castle for Java](https://junglewise.ai/threats/technologies/bouncy-castle-for-java). Vendors: [Bouncy Castle](https://junglewise.ai/threats/vendors/bouncy-castle).

## Quick answers

**Is CVE-2026-59645 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-59645 being exploited in the wild.

**How severe is CVE-2026-59645?** 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; Bouncy Castle for Java FIPS (bcutil-fips) 2.0.X before 2.0.7, 2.1.X before 2.1.7.

**Is there a fix for CVE-2026-59645?** 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.

**Am I affected by CVE-2026-59645?** Check whether you run Bouncy Castle for Java or Bouncy Castle for Java FIPS (bcutil-fips) 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 stack overflow / denial-of-service issue in the OER (Octet Encoding Rules) parser when processing self-referential schemas defined in IEEE 1609.2 (a standard for vehicular communications). The parser lacks depth-limiting safeguards and will recurse without bound on specially crafted input containing circular schema references. An attacker can send a network packet or malicious serialized object containing a self-referential IEEE 1609.2 schema to any application parsing untrusted OER-encoded data. No authentication is required; network accessibility to the vulnerable parser is the primary precondition. Successful exploitation causes denial-of-service through resource exhaustion. Patches are available: upgrade to Bouncy Castle for Java 1.85+, Java LTS 2.73.12+, or BC-FJA bcutil-fips 2.0.7 (2.0.X) / 2.1.7 (2.1.X).

## 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 (bcutil-fips) 2.0.X before 2.0.7, 2.1.X before 2.1.7

## Timeline

- 2026-08-03: disclosed: CVE-2026-59645 published

## References

- [https://www.bouncycastle.org/download/bouncy-castle-java/](https://www.bouncycastle.org/download/bouncy-castle-java/)
- [https://www.bouncycastle.org/download/bouncy-castle-java-lts/](https://www.bouncycastle.org/download/bouncy-castle-java-lts/)

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