ERPNext v15.103.1 and before is vulnerable to Server-Side Template Injection (SSTI). An attacker with permission to create or edit email templates can inject template expressions that are executed on the server when the template is rendered.
Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:HI:HA:H9.8/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H