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.
Scoring
- Severity
- HIGH
- CVSS base score
- 8.7
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/U:Amber
- EPSS probability
- 0.17%
- CWE
- CWE-354
- Published
- 2026-08-03
- Last modified
- 2026-08-03
Affected products
- Legion of the Bouncy Castle Inc. BC-JAVA
- Legion of the Bouncy Castle Inc. BC-LTS-JAVA
Weakness type
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