Malicious HTML content could be injected into the email address of an order, which pretix showed without sanitization on the confirmation page for individual tickets in that order.
Exploitability
AV:NAC:LAT:NPR:NUI:PVulnerable System
VC:LVI:LVA:LSubsequent System
SC:LSI:LSA:L5.3/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:LOther