What’s Vulnerable › Vulnerabilities

CVE-2020-15522

• Severity: medium (CVSS 5.9 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-05-20 · updated 2026-06-17
• Weakness: CWE-362

Description

Bouncy Castle BC Java before 1.66, BC C# .NET before 1.8.7, BC-FJA before 1.0.1.2, 1.0.2.1, and BC-FNA before 1.0.1.1 have a timing issue within the EC math library that can expose information about the private key when an attacker is able to observe timing information for the generation of multiple deterministic ECDSA signatures.

Affected products

• Legion of the Bouncy Castle Inc. bc-csharp: before 1.8.7 — fixed in 1.8.7
• Bouncycastle Bouncy Castle Fips .Net Api: before 1.0.1.1 — fixed in 1.0.1.1
• Bouncycastle Fips Java Api: before 1.0.1.2; from 1.0.2 before 1.0.2.1 — fixed in 1.0.1.2, 1.0.2.1
• Bouncycastle The Bouncy Castle Crypto Package For Java: before 1.66 — fixed in 1.66

How to fix

Upgrade to a fixed version: Legion of the Bouncy Castle Inc. bc-csharp 1.8.7; Bouncycastle Bouncy Castle Fips .Net Api 1.0.1.1; Bouncycastle Fips Java Api 1.0.1.2, 1.0.2.1; Bouncycastle The Bouncy Castle Crypto Package For Java 1.66. Check the vendor advisory for mitigations.

References

• https://github.com/bcgit/bc-csharp/wiki/CVE-2020-15522
• https://github.com/bcgit/bc-java/wiki/CVE-2020-15522
• https://security.netapp.com/advisory/ntap-20210622-0007/
• https://www.bouncycastle.org/releasenotes.html
• https://github.com/bcgit/bc-csharp/wiki/CVE-2020-15522
• https://github.com/bcgit/bc-java/wiki/CVE-2020-15522
• https://security.netapp.com/advisory/ntap-20210622-0007/
• https://www.bouncycastle.org/releasenotes.html

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