Affected versions of Flowintel construct timeline HTML using attacker-controllable MISP object fields such as:
*
object UUID;
*
object name;
*
attribute value;
*
attribute type;
*
comment;
*
first/last seen values;
*
IDS flag.
Those values were concatenated directly into HTML strings before rendering. The upstream commit explicitly states that DOMPurify removed XSS vectors but still allowed other HTML elements, such as forms, through.
The fix replaces direct string interpolation with DOM construction via document.createElement() and assigns all attacker-controlled values using textContent. The headline is similarly converted to escaped HTML through a temporary element.
Version impacted =>3.3.0