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Fencer Intel
high 7.6

CVE-2021-42360 json

Starter Templates — Elementor, Gutenberg & Beaver Builder Templates <= 2.7.0 Authenticated Block Import to Stored XSS

published 4y ago modified 4mo ago also EUVD-2021-29331

cvss
7.6
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 49%
public exploits
0
none known

Summary

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.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.60% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • wordfence.com https://www.wordfence.com/blog/2021/11/over-1-million-sites-impacted-by-vulnerability-in-starter-templates-plugin/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.6 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L
NVD 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 3.5 AV:N/AC:M/Au:S/C:N/I:P/A:N

Affected products

  • BrainStormForce Starter Templates — Elementor, Gutenberg & Beaver Builder Templates

Classification

Weakness
  • CWE-284 Improper Access Control
  • CWE-79 Improper Neutralization of Input During Web Page Generation
  • CWE-99 Improper Control of Resource Identifiers
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.