CVE-2021-42360: brainstormforce starter_templates Cross-site Scripting
Vulnerability summary
CVE-2021-42360 is a high (CVSS 7.6) Cross-site Scripting vulnerability in brainstormforce starter_templates. EPSS estimates a 0.60% chance of exploitation in the next 30 days, higher than 47.8% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 17-11-2021PublishedVulnerability first disclosed.
- 14-02-2025Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
4 scores · 3 sources · 2 versions- NVDNIST5.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:NDiffers
- wordfenceSource7.6HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L
EPSS trend
Probability
0.60%
Chance of exploitation in the next 30 days
Percentile
48%
Versus all other CVEs
30-day change
0.00 pp
From 0.60% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (wordfence.com)
Maturity: unknown
Weaknesses
CWE · root cause- CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
- CWE-99Improper Control of Resource Identifiers ('Resource Injection')The product receives input from an upstream component, but it does not restrict or incorrectly restricts the input before it is used as an identifier for a resource that may be outside the intended sphere of control.
- CWE-284Improper Access ControlThe product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
- CWE-862Missing AuthorizationThe product does not perform an authorization check when an actor attempts to access a resource or perform an action.
Affected systems
Brainstormforce2 products
Wordpress1 product
- astra-sites≤ 2.7.0 (fixed in 2.7.1)
2 vendors · 3 products