In the Bouncy Castle JCE Provider version 1.55 and earlier the other party DH public key is not fully validated. This can cause issues as invalid keys can be used to reveal details about the other party's private key where static Diffie-Hellman is in use. As of release 1.56 the key parameters are checked on agreement calculation.
https://access.redhat.com/errata/RHSA-2018:2669
https://access.redhat.com/errata/RHSA-2018:2927
https://lists.debian.org/debian-lts-announce/2018/07/msg00009.html
https://security.netapp.com/advisory/ntap-20181127-0004/
Source: MITRE
Published: 2018-06-04
Updated: 2020-10-20
Type: CWE-320
Base Score: 4.3
Vector: AV:N/AC:M/Au:N/C:P/I:N/A:N
Impact Score: 2.9
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 3.7
Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Impact Score: 1.4
Exploitability Score: 2.2
Severity: LOW