Jenkins 2.483 through 2.550 (both inclusive), LTS 2.492.1 through 2.541.1 (both inclusive) does not escape the user-provided description of the "Mark temporarily offline" offline cause, resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers with Agent/Configure or Agent/Disconnect permission.
Exploitability
AV:NAC:LPR:LUI:RScope
S:UImpact
C:HI:HA:H8/CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H