Jervis is a library for Job DSL plugin scripts and shared Jenkins pipeline libraries. Prior to 2.2, the salt is derived from sha256Sum(passphrase). Two encryption operations with the same password will have the same derived key. This vulnerability is fixed in 2.2.
Exploitability
AV:NAC:LAT:NPR:NUI:NVulnerable System
VC:HVI:NVA:NSubsequent System
SC:NSI:NSA:N8.7/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NCryptography