RCE Security Advisory
1. ADVISORY INFORMATION
Product: Quiz And Survey Master
Vendor URL: https://wordpress.org/plugins/quiz-master-next/
Type: Cross-Site Request Forgery (CSRF) [CWE-352]
Date found: 2023-01-13
Date published: 2023-02-08
CVSSv3 Score: 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N)
This vulnerability was discovered and researched by Julien Ahrens from
3. VERSIONS AFFECTED
Quiz And Survey Master 8.0.8 and below
Quiz and Survey Master is the easiest WordPress Quiz Plugin which can be used
to create engaging content to drive traffic and increase user engagement.
Everything from viral quiz, trivia quiz, customer satisfaction surveys to employee
surveys. This plugin is the ultimate marketing tool for your website.
(from the vendor’s homepage)
5. VULNERABILITY DETAILS
The plugin offers the ajax action “qsm_remove_file_fd_question” which is used to
delete uploaded media contents from the WordPress instance. However, the
functionality is not protected by an anti-CSRF token/nonce.
Since there is no anti-CSRF token protecting this functionality, it is vulnerable
to Cross-Site Request Forgery attacks allowing an attacker to delete uploaded
media contents on behalf of the attacked user.
To successfully exploit this vulnerability, a user with the right to access the
plugin must be tricked into visiting an arbitrary website while having an
authenticated session in the application.
6. PROOF OF CONCEPT
The following Proof-of-Concept would delete the uploaded media with the ID “1”:
history.pushState(”, ”, ‘/’)
Update to version 8.0.9
8. REPORT TIMELINE
2023-01-13: Discovery of the vulnerability
2023-01-13: Wordfence (responsible CNA) assigns CVE-2023-0291
2023-01-18: Sent initial notification to vendor via contact form
2022-01-18: Vendor response
2022-01-21: Vendor releases version 8.0.9 which fixes the vulnerability
2022-02-08: Public disclosure