delayed_job_web rails gem XSS vulnerability

Summary

An exploitable XSS vulnerability exists in the filter functionality of the delayed_job_web rails gem version 1.4. A specially crafted URL can cause an XSS flaw resulting in an attacker being able to execute arbitrary javascript on the victim’s browser. An attacker can phish an authenticated user to trigger this vulnerability.

Tested Versions

delayed_job_web 1.4

Product URLs

https://github.com/ejschmitt/delayed_job_web https://rubygems.org/gems/delayed_job_web/versions/1.4

CVSSv3 Score

6.1 - CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CWE

CWE-79: Improper Neutralization of Input During Web Page Generation (‘Cross-site Scripting’)

Details

The delayed_job_web gem allows users to filter output based on the query string of the GET request. This looks similar to.

localhost:3000/delayed_job/overview?queues=”>+<script>alert(1)<%2Fscript>

This URL can them be used to phish an authenticated user and execute arbitrary javascript on their behalf. This vulnerability is caught by the built in XSS protections of Safari and Chrome., however it is exploitable using Firefox.

Credit

Discovered by Zachary Sanchez of Cisco ASIG

Timeline

2017-09-20 - Vendor Disclosure
2018-01-09 - Public Release