[revive-adserver] Reflected XSS in Banner Delivery Options via cap parameter

Summary

Security advisory: REVIVE-SA-2026-001

Description

HackerOne community member Patrick Lang (7yr) has reported a reflected XSS vulnerability in the banner-acl.php script of Revive Adserver. An attacker can craft a specific URL that includes an HTML payload in a parameter. If a logged in administrator visits the URL, the HTML is sent to the browser and malicious scripts would be executed.

Details

The cap, session_capping and time request parameters sent to the banner-acl.php script were used in the output without proper sanitisation, allowing an attacker to craft specific URLs and have payloads output in the HTML, JS, and/or CSS context. Successful exploitation requires an attacker to trick a logged in user into visiting the crafted URL.