CVE-2026-109396 [MEDIUM] – Thelia before 3.1.2 and 3.2.x before 3.2.1 contains a CSV formula injection vulnerability

Thelia before 3.1.2 and 3.2.x before 3.2.1 contains a CSV formula injection vulnerability that allows unauthenticated visitors to inject spreadsheet formulas by supplying crafted registration, checkout or newsletter fields. Attackers can submit names, addresses or phone values starting with =, +, – or @ that CSVSerializer exports verbatim, executing formulas in the administrator’s spreadsheet application.