Medium (4.4). EPSS 0.3% chance of exploitation in the next 30 days. Fixed in org.bouncycastle:bcprov-jdk15on 1.50.
The default BKS keystore use an HMAC that is only 16 bits long, which can allow an attacker to compromise the integrity of a BKS keystore. Bouncy Castle release 1.47 changes the BKS format to a format which uses a 160 bit HMAC instead. This applies to any BKS keystore generated prior to BC 1.47. For situations where people need to create the files for legacy reasons a specific keystore type "BKS-V1" was introduced in 1.49. It should be noted that the use of "BKS-V1" is discouraged by the library authors and should only be used where it is otherwise safe to do so, as in where the use of a 16 bit checksum for the file integrity check is not going to cause a security issue in itself.
Severity
CVSS 3.1
4.4 medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
EPSS
0.3% chance of exploitation in the next 30 days; higher than 17% of CVEs (scores of 2026-10-31)