CVE-2024-34064

A flaw was found in jinja2. The xmlattr filter accepts keys containing non-attribute characters. XML/HTML attributes cannot contain spaces, /, >, or =, as each would then be interpreted as starting a separate attribute. If an application accepts keys (as opposed to only values) as user input, and renders these in pages that other users see as well, an attacker could inject other attributes and perform cross-site scripting (XSS).

Mitigation

Do not accept user input as keys to the xmlattr filter without validation. See the statement above for more information.