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Vulnerability record · CVE-2020-15522 · published 20 May 2021

CVE-2020-15522: Bouncycastle bc-csharp race condition vulnerability

Bouncycastle · Bc Csharp

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.

5.9 CVSS 3.1 Medium EPSS 1.5% · top 25.0% CWE-362 · Race condition
5.9CVSS 3.1 base score, v2 4.3
1.5%EPSS exploitation probability, 30 days
NoNot in CISA KEV
4Affected product versions listed by NVD
8References
17 Jun 2026Last modified by NVD

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.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products

4 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/bcgit/bc-csharp/wiki/CVE-2020-15522 Third Party Advisory
https://github.com/bcgit/bc-java/wiki/CVE-2020-15522 Third Party Advisory
https://security.netapp.com/advisory/ntap-20210622-0007/
https://www.bouncycastle.org/releasenotes.html Release NotesVendor Advisory
https://github.com/bcgit/bc-csharp/wiki/CVE-2020-15522 Third Party Advisory
https://github.com/bcgit/bc-java/wiki/CVE-2020-15522 Third Party Advisory
https://security.netapp.com/advisory/ntap-20210622-0007/
https://www.bouncycastle.org/releasenotes.html Release NotesVendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2020-15522), CISA KEV, FIRST EPSS (scores of 2026-11-14). This page is refreshed as NVD updates the record.