XSS in Brainstormforce Starter Templates
CVE-2021-42360
On sites that also had the Elementor plugin for WordPress installed, it was possible for users with the edit_posts capability, which includes Contributor-level users, to import blocks onto any page using the astra-page-elementor-batch-process AJAX action. An attacker could craft and host a block containing malicious JavaScript on a server they controlled, and then use it to overwrite any post or page by sending an AJAX request with the action set to astra-page-elementor-batch-process and the url parameter pointed to their remotely-hosted malicious block, as well as an id parameter containing the post or page to overwrite. Any post or page that had been built with Elementor, including published pages, could be overwritten by the imported block, and the malicious JavaScript in the imported block would then be executed in the browser of any visitors to that page.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.006 (45.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L.
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@wordfence.com (Exploit, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2021-42360?
- CVE-2021-42360 is a high-severity vulnerability in Brainstormforce Starter Templates, classified under Cross-site Scripting. CVSS score: 7.6/10. Published 2021-11-17.
- How severe is CVE-2021-42360?
- High severity. CVSS v3 base score is 7.6 out of 10.
- Is CVE-2021-42360 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.