CVE-2026-105456: Stored XSS via HTML scrubber rule in RTIR

RTIR extends RT's HTML scrubber to allow an internal link placeholder, and the extension lets through any link that merely contains the placeholder, including links using the executable javascript: scheme. The change applies to the whole RT instance once RTIR is installed, not only to RTIR's own queues. Anyone who can add HTML content to a ticket on such an instance can store such a link. That includes an unauthenticated sender of HTML email to the Incident Reports queue, which RTIR opens to everyone by default. Script runs when a user clicks the link, in that user's session, and can act in RT with that user's authority.

This issue was fixed in version 5.0.11 and 6.0.4