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 Legion of the Bouncy Castle Inc.'s BC-JAVA library. It affects versions prior to 1.85 and certain 2.73.x LTS versions before 2.73.12. 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 Bouncy Castle for Java occurs because CMS AuthenticatedData content is not properly bound to the MAC when authenticated attributes (authAttrs) are present. Affected versions include all before 1.85, and LTS versions from 2.73.0 up to but not including 2.73.12. The flaw means that the integrity check value can be improperly validated, potentially allowing attackers to bypass integrity protections. The vulnerability also affects Bouncy Castle for Java FIPS versions before specified patch releases in the 1.0.X, 2.0.X, and 2.1.X series. No official remediation level or patch links are provided in the source data.
Potential Impact
The vulnerability compromises the integrity validation of CMS AuthenticatedData, which could allow an attacker to manipulate or tamper with authenticated content without detection. This undermines the cryptographic assurances provided by the library, potentially impacting any application relying on Bouncy Castle for secure message authentication. The CVSS 4.0 score of 8.7 (high severity) reflects the network attack vector, low attack complexity, no privileges or user interaction required, and high impact on integrity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official patch or remediation level is provided in the available data, users should monitor the Legion of Bouncy Castle Inc. advisories for updates. Until a fix is available, consider avoiding use of affected versions or applying any recommended workarounds from the vendor.
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 Legion of the Bouncy Castle Inc.'s BC-JAVA library. It affects versions prior to 1.85 and certain 2.73.x LTS versions before 2.73.12. 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
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 Bouncy Castle for Java occurs because CMS AuthenticatedData content is not properly bound to the MAC when authenticated attributes (authAttrs) are present. Affected versions include all before 1.85, and LTS versions from 2.73.0 up to but not including 2.73.12. The flaw means that the integrity check value can be improperly validated, potentially allowing attackers to bypass integrity protections. The vulnerability also affects Bouncy Castle for Java FIPS versions before specified patch releases in the 1.0.X, 2.0.X, and 2.1.X series. No official remediation level or patch links are provided in the source data.
Potential Impact
The vulnerability compromises the integrity validation of CMS AuthenticatedData, which could allow an attacker to manipulate or tamper with authenticated content without detection. This undermines the cryptographic assurances provided by the library, potentially impacting any application relying on Bouncy Castle for secure message authentication. The CVSS 4.0 score of 8.7 (high severity) reflects the network attack vector, low attack complexity, no privileges or user interaction required, and high impact on integrity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official patch or remediation level is provided in the available data, users should monitor the Legion of Bouncy Castle Inc. advisories for updates. Until a fix is available, consider avoiding use of affected versions or applying any recommended workarounds from the vendor.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- bcorg
- Date Reserved
- 2026-07-06T06:58:29.263Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a6fe8f1bf32cb7a34b61c9f
Added to database: 08/03/2026, 01:03:45 UTC
Last enriched: 08/03/2026, 01:19:26 UTC
Last updated: 08/03/2026, 02:03:19 UTC
Views: 3
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