Jervis is a library for Job DSL plugin scripts and shared Jenkins pipeline libraries. Prior to 2.2, Jervis uses padLeft(32, '0') when it should use padLeft(64, '0') because SHA-256 produces 32 bytes which equates to 64 hex characters. This vulnerability is fixed in 2.2.
Exploitability
AV:NAC:LAT:NPR:NUI:NVulnerable System
VC:NVI:HVA:NSubsequent System
SC:NSI:NSA:N8.7/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:NCryptography