CVE-2020-15522

Name: CVE-2020-15522
Creator: NVD / NIST
Published: 2021-05-20T12:15:08.003+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.9/10EPSS 1.52%

Last modified Jun 17, 2026

CVE-2020-15522 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. 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.. EPSS estimates a 1.52% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

5.9/10

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

EPSS Probability

1.52%

71.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-362

Affected Software

Vendor	Product	Versions
Bouncycastle	Bc-Csharp	< 1.8.7
Bouncycastle	Bouncy Castle Fips .Net Api	< 1.0.1.1
Bouncycastle	Fips Java Api	< 1.0.1.2
Bouncycastle	Fips Java Api	>= 1.0.2, < 1.0.2.1
Bouncycastle	The Bouncy Castle Crypto Package For Java	< 1.66

References

https://github.com/bcgit/bc-csharp/wiki/CVE-2020-15522Third Party Advisory
https://github.com/bcgit/bc-java/wiki/CVE-2020-15522Third Party Advisory
https://security.netapp.com/advisory/ntap-20210622-0007/
https://www.bouncycastle.org/releasenotes.htmlRelease Notes, Vendor Advisory
https://github.com/bcgit/bc-csharp/wiki/CVE-2020-15522Third Party Advisory
https://github.com/bcgit/bc-java/wiki/CVE-2020-15522Third Party Advisory
https://security.netapp.com/advisory/ntap-20210622-0007/
https://www.bouncycastle.org/releasenotes.htmlRelease Notes, Vendor Advisory

Timeline

Published: May 20, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-15522?

How severe is CVE-2020-15522?

CVE-2020-15522 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 1.52% probability of exploitation in the next 30 days.

How do I fix CVE-2020-15522?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-15522?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST