CVE-2026-59639

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).

  • Published Aug 3, 2026
  • CVSS 8.7 high
  • 0.2% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

In the news

CVE-2026-59639 at the National Vulnerability Database