Unbounded HSS Public-Key Level Count in Bouncy Castle for Java by Bouncy Castle
CVE-2026-58060

8.7HIGH

Key Information:

Vendor

Legion Of The Bouncy Castle Inc.

Status
Bc-java
Bc-lts-java
Bc-fja
Vendor
CVE Published:
3 August 2026

What is CVE-2026-58060?

A vulnerability has been identified in Bouncy Castle for Java versions prior to 1.85, where the HSS public-key level count is unbounded. This flaw can result in excessive resource allocation during the verification process, potentially leading to denial-of-service conditions. The issue is also present in Bouncy Castle for Java LTS prior to version 2.73.12 and in the FIPS version before 2.0.2 in the 2.0.X series and 2.1.3 in the 2.1.X series. Users are advised to upgrade to the latest version to mitigate the risk associated with this vulnerability.

Affected Version(s)

BC-FJA all 2.0.0 < 2.0.2

BC-FJA all 2.1.0 < 2.1.3

BC-JAVA all 1.65 < 1.85

References

https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2...
vendor-advisory
https://github.com/bcgit/bc-java/commit/311cabbb6fcead764...
patch
https://github.com/bcgit/bc-java/commit/6c9f30b3fdaa3f214...
patch

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Alex Gaynor in collaboration with Claude and Anthropic Research
.