Instant CSS <= 1.1.4 - Missing Authorization via AJAX Actions

Missing Authorization
CVE CVE-2023-38483
CVSS Medium (5.3)
Publicly Published July 24, 2023
Last Updated January 22, 2024
Researcher Abdi Pranata
Description

The Instant CSS plugin for WordPress is vulnerable to unauthorized access and modification of data due to missing capability checks on several functions called via AJAX actions in the ~/classes/class.instantcss_ajax.php file in versions up to, and including, 1.1.4. This makes it possible for authenticated attackers, with subscriber-level access and above, to perform a wide variety of actions such as retrieving css, theme, and minify data, along with updating the options for those. The unprotected AJAX actions present can be used to exploit a site via Cross-Site Scripting as well.

References

1 affected software package

Software Type Plugin
Software Slug instant-css (view on wordpress.org)
Patched? Yes
Affected Version
  • <= 1.1.4
Patched Version
  • 1.1.5
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