FirstBlood-#789 — Reflective XSS at /register.php
This issue was discovered on FirstBlood v2
On 2021-10-28, 0xirfan Level 5 reported:
The ref paramter in the /register.php is Vulnerable to XSS. The input Provided in the ref parameter is reflected at href value of an anchor tag.
for the XSS to trigger the Victim need to Click at the Return to previous page Link
Finding the Payload
1) Just Send this URL to the Victim
2)if the Victim Clicks the Return to previous page Link. XSS will be triggered
The XSS can be used to steal cookies which leads to ATO
FirstBlood ID: 32
Vulnerability Type: Reflective XSS
The parameter ?ref on register.php was poorly fixed and can be bypassed in various ways. Firstly the developer failed to use strtolower() when comparing strings, and the use of characters such as
%09 will also bypass the filter.