CVE-2026-59642: CWE-354 Improper Validation of Integrity Check Value in Legion of the Bouncy Castle Inc. BC-JAVA
CVE-2026-59642 is a high-severity vulnerability in Bouncy Castle for Java (BC-JAVA) affecting versions before 1.85 and certain LTS and FIPS versions prior to specified patch releases. The issue involves improper validation of the integrity check value in CMS AuthenticatedData when authenticated attributes are present, meaning the content is not properly bound to the MAC. This could undermine the integrity guarantees of the cryptographic message syntax implementation.
AI Analysis
Technical Summary
This vulnerability (CWE-354) in BC-JAVA occurs because CMS AuthenticatedData content is not bound to the MAC when authenticated attributes (authAttrs) are present. Affected versions include BC-JAVA before 1.85, BC-JAVA LTS versions from 2.73.0 up to but not including 2.73.12, and BC-FJA FIPS versions before bcpkix-fips 1.0.12 (1.0.X series), 2.0.12 (2.0.X series), and 2.1.12 (2.1.X series). The flaw allows an attacker to potentially bypass integrity checks, compromising data integrity verification in cryptographic operations.
Potential Impact
The vulnerability compromises the integrity validation of CMS AuthenticatedData in affected BC-JAVA versions, potentially allowing attackers to tamper with data without detection. This undermines the cryptographic assurances provided by the library, which could affect any applications relying on BC-JAVA for secure message authentication. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is indicated in the provided data. Users should monitor the Legion of the Bouncy Castle Inc. advisories for updates and apply patches once available.
CVE-2026-59642: CWE-354 Improper Validation of Integrity Check Value in Legion of the Bouncy Castle Inc. BC-JAVA
Description
CVE-2026-59642 is a high-severity vulnerability in Bouncy Castle for Java (BC-JAVA) affecting versions before 1.85 and certain LTS and FIPS versions prior to specified patch releases. The issue involves improper validation of the integrity check value in CMS AuthenticatedData when authenticated attributes are present, meaning the content is not properly bound to the MAC. This could undermine the integrity guarantees of the cryptographic message syntax implementation.
CVSS v4.0
Score 8.7high
Affected software
Legion of the Bouncy Castle Inc.
BC-JAVA
Legion of the Bouncy Castle Inc.
BC-LTS-JAVA
Legion of the Bouncy Castle Inc.
BC-FJA
pkg:github/bcpkix-lts8onRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-354) in BC-JAVA occurs because CMS AuthenticatedData content is not bound to the MAC when authenticated attributes (authAttrs) are present. Affected versions include BC-JAVA before 1.85, BC-JAVA LTS versions from 2.73.0 up to but not including 2.73.12, and BC-FJA FIPS versions before bcpkix-fips 1.0.12 (1.0.X series), 2.0.12 (2.0.X series), and 2.1.12 (2.1.X series). The flaw allows an attacker to potentially bypass integrity checks, compromising data integrity verification in cryptographic operations.
Potential Impact
The vulnerability compromises the integrity validation of CMS AuthenticatedData in affected BC-JAVA versions, potentially allowing attackers to tamper with data without detection. This undermines the cryptographic assurances provided by the library, which could affect any applications relying on BC-JAVA for secure message authentication. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is indicated in the provided data. Users should monitor the Legion of the Bouncy Castle Inc. advisories for updates and apply patches once available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- bcorg
- Date Reserved
- 2026-07-06T06:58:29.263Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a6fe8f1bf32cb7a34b61c9f
Added to database: 08/03/2026, 01:03:45 UTC
Last enriched: 08/10/2026, 15:26:05 UTC
Last updated: 09/16/2026, 10:01:33 UTC
Views: 40
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