Description
In Bouncy Castle for Java before 1.85, IESEngine stream-mode MAC forgery via length-dependent KDF split. This issue also affects Bouncy Castle for Java LTS before 2.73.12.
Affected products
bouncycastle: bc-java; bouncycastle: bouncy castle for java lts
References2
- github.com/bcgit/bc-java/commit/6d9e4bbaee9409713ada167e5f90155… Patch
- github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9012816 Third Party AdvisoryPatch
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 4.0
-
8.7
HIGH
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber - EPSS — exploit probability
- 0% percentile: 8 · as of 13 November 2026
- CWE
- CWE-354
Could this be exploited in your environment?
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