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6.4Medium

CVE-2026-13203

The Live Composer – Free WordPress Website Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'custom_id' shortcode attribute of the dslc_modules_section and dslc_modules_area shortcodes in versions up to, and including, 2.1.19. This is due to insufficient input sanitization and output escaping on the user-supplied attribute, which is concatenated into the HTML id="" attribute of the rendered element in the dslc_modules_section_front() and dslc_modules_area_front() functions without esc_attr(). This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

What this means for your business

  • An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 15% of all known flaws.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Check if you’re exposedBook a call

Scoring

CVSS
6.4 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Weakness
CWE-79
Assigned by
security@wordfence.com

Dates

Published
2026-09-01
Last modified
2026-09-01
Sources
NVD

References