In Bouncy Castle for Java before 1.85, KCCMBlockCipher MAC does not bind nonce when AAD is absent (cross-nonce AEAD forgery). (CVE-2026-12803)
In Bouncy Castle for Java before 1.85, KCCMBlockCipher MAC does not bind nonce when AAD is absent (cross-nonce AEAD forgery). This issue also affects Bouncy Castle for Java LTS before 2.73.12.
In Bouncy Castle for Java before 1.85, KCCMBlockCipher MAC does not bind nonce when AAD is absent (cross-nonce AEAD forgery). (CVE-2026-12803)
Description
In Bouncy Castle for Java before 1.85, KCCMBlockCipher MAC does not bind nonce when AAD is absent (cross-nonce AEAD forgery). This issue also affects Bouncy Castle for Java LTS before 2.73.12.
CVSS v4.0
Weaknesses
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-4r33-j73q-cw77
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-12803"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 4.0
Threat ID: 6a710683bf32cb7a343985c8
Added to database: 08/03/2026, 21:22:11 UTC
Last updated: 08/03/2026, 21:22:11 UTC
Views: 1
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