CVE-2026-59639 (GCVE-0-2026-59639)

Vulnerability from cvelistv5 – Published: 2026-08-03 00:56 – Updated: 2026-08-03 13:24
VLAI
Title
CMS verifySignatures returns true for SignedData with zero signers
Summary
In Bouncy Castle for Java before 1.85, CMS verifySignatures returns true for SignedData with zero signers. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) 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).
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
Impacted products
Vendor Product Version
Legion of the Bouncy Castle Inc. BC-JAVA Affected: 0 , < 1.85 (maven)
Create a notification for this product.
Legion of the Bouncy Castle Inc. BC-LTS-JAVA Affected: 2.73.0 , < 2.73.12 (maven)
Create a notification for this product.
Legion of the Bouncy Castle Inc. BC-FJA Affected: 1.0.0 , < 1.0.12 (maven)
Affected: 2.0.0 , < 2.0.12 (maven)
Affected: 2.1.0 , < 2.1.12 (maven)
Create a notification for this product.
Credits
Alex Gaynor in collaboration with Claude and Anthropic Research
Show details on NVD website

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