Multiple vulnerabilities on Meta4 HR from Cegid

A Cross-Site Scripting Vulnerability has been found on Meta4 HR affecting version 819.001.022 and earlier. The endpoint '/sse_generico/generico_login.jsp' is vulnerable to XSS attack via 'lang' query, i.e. '/sse_generico/generico_login.jsp?lang=%27%3balert(%27BLEUSS%27)%2f%2f&params='.