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Vulnerability record · CVE-2026-59644 · published 3 August 2026

CVE-2026-59644: Bouncycastle bc-java vulnerability

Bouncycastle · Bc Java

In Bouncy Castle for Java before 1.85, MLS hash-ratchet honours arbitrary 32-bit generation counter from sender.

8.7 CVSS 4.0 High EPSS 0.49% · top 60.1% CWE-834 · CWE-834
8.7CVSS 4.0 base score
0.49%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
31 Aug 2026Last modified by NVD

Description

In Bouncy Castle for Java before 1.85, MLS hash-ratchet honours arbitrary 32-bit generation counter from sender.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

Affected products

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

References

LinkTags
https://github.com/bcgit/bc-java/commit/610d8757d855afe197df0de6d831cb75c81e3b9f Patch
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059644 Third Party 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-2026-59644), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.