# CVE-2026-5588: bouncycastle: Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc

CVE-2026-5588 is fixed in 7 products on 1 platform, first by DEBIAN-CVE-2026-5588, released April 15, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-5588
- Priority: Routine
- CVSS: n/a (moderate)
- EPSS: 0.0078
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 15, 2026

## Description

Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules), Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All (pkix modules), Legion of the Bouncy Castle Inc. BCPIX-LTS bcpkix on All (pkix modules).   This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java, JcaContentVerfierProviderBuilder.Java.    This issue affects BC-JAVA: from 1.67 before 1.80.2, from 1.81 before 1.81.1, from 1.82 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11; BCPIX-LTS: from 2.73.7 before 2.73.11.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bouncycastle Debian 14 | 1.86-1 | [DEBIAN-CVE-2026-5588](https://patchblox.com/security/data/fix/linux/debian-cve-2026-5588.md) | Apr 15, 2026 |
| Linux | bouncycastle amzn 2023 | 1.70-4.amzn2023.0.7 | [ALAS2023-2026-1775](https://patchblox.com/security/data/fix/linux/alas2023-2026-1775.md) | Jun 8, 2026 |
| Linux | bouncycastle-javadoc amzn 2023 | 1.70-4.amzn2023.0.7 | [ALAS2023-2026-1775](https://patchblox.com/security/data/fix/linux/alas2023-2026-1775.md) | Jun 8, 2026 |
| Linux | bouncycastle-mail amzn 2023 | 1.70-4.amzn2023.0.7 | [ALAS2023-2026-1775](https://patchblox.com/security/data/fix/linux/alas2023-2026-1775.md) | Jun 8, 2026 |
| Linux | bouncycastle-pg amzn 2023 | 1.70-4.amzn2023.0.7 | [ALAS2023-2026-1775](https://patchblox.com/security/data/fix/linux/alas2023-2026-1775.md) | Jun 8, 2026 |
| Linux | bouncycastle-pkix amzn 2023 | 1.70-4.amzn2023.0.7 | [ALAS2023-2026-1775](https://patchblox.com/security/data/fix/linux/alas2023-2026-1775.md) | Jun 8, 2026 |
| Linux | bouncycastle-tls amzn 2023 | 1.70-4.amzn2023.0.7 | [ALAS2023-2026-1775](https://patchblox.com/security/data/fix/linux/alas2023-2026-1775.md) | Jun 8, 2026 |
| Linux | bouncycastle-util amzn 2023 | 1.70-4.amzn2023.0.7 | [ALAS2023-2026-1775](https://patchblox.com/security/data/fix/linux/alas2023-2026-1775.md) | Jun 8, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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