CVE-2025-5533

Knowledge Base <= 2.3.0 - Authenticated (Contributor+) Stored Cross-Site Scripting

Published Jun 6, 2025 CVSS 3.1 · 6.4 Medium EPSS < 1% KEV · Not listed
Description
The Knowledge Base plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'kbalert' shortcode in all versions up to, and including, 2.3.0 due to insufficient input sanitization and output escaping on user supplied attributes. 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.

Analysis

AI-generated

Technical impact

The Knowledge Base plugin for WordPress is vulnerable to stored cross‑site scripting because user‑supplied attributes in the "kbalert" shortcode are not properly sanitized or escaped. An attacker with contributor privileges can embed arbitrary JavaScript that will run whenever a user views a page containing the injected shortcode. This flaw may lead to session hijacking, defacement, or theft of sensitive information from site visitors, compromising confidentiality and integrity.

Affected Systems

All instances of the Knowledge Base WordPress plugin with versions 2.3.0 or earlier are susceptible. The vulnerability exists across all WordPress installations that have installed any of these affected versions of the plugin, regardless of other configuration settings.

Risk and Exploitability

The flaw has a CVSS score of 6.4, indicating moderate severity. Because the EPSS score is reported as less than 1%, the likelihood of exploitation is considered low at present, and the vulnerability is not listed in the CISA KEV catalog. Nevertheless, the attack vector requires an authenticated user with contributor-level access or higher, who can inject malicious code via the kbalert shortcode. Once injected, the script executes automatically for any visitor to the affected page, making it a significant risk for sites with larger user bases or high traffic.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade to the latest version of the Knowledge Base plugin (at least 2.3.1 or newer) to address the input sanitization flaw.
  • If an upgrade is not immediately possible, remove or disable the "kbalert" shortcode from your content or configure the plugin to reject all user‑supplied attributes until a patch is available.
  • Reduce the number of users with contributor or higher roles, or enforce stricter role permissions, so that fewer accounts can insert or edit shortcode content.

Generated by OpenCVE AI on April 21, 2026 at 20:25 UTC.

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2025-17083 The Knowledge Base plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'kbalert' shortcode in all versions up to, and including, 2.3.0 due to insufficient input sanitization and output escaping on user supplied attributes. 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.
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description The Knowledge Base plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'kbalert' shortcode in all versions up to, and including, 2.3.0 due to insufficient input sanitization and output escaping on user supplied attributes. 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.
Title Knowledge Base <= 2.3.0 - Authenticated (Contributor+) Stored Cross-Site Scripting
Weaknesses CWE-79
References
Metrics cvssV3_1

{'score': 6.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N'}

Subscriptions

No data.

Weaknesses
  • CWE-79

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Sources

Status
PUBLISHED
Assigner
Wordfence
Published
Updated
Apr 8, 2026, 4:48 PM
Reserved
Jun 3, 2025, 2:59 PM
Status
Deferred
Published
Jun 6, 2025, 7:15 AM
Modified
Jun 17, 2026, 9:48 AM