CVE-2026-12561: tagdiv tagdiv_composer Cross-site Scripting

Vulnerability summary

CVE-2026-12561 is a medium (CVSS 6.4) Cross-site Scripting vulnerability in tagdiv tagdiv_composer. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 6.5% of scored vulnerabilities. Fixed in 5.4.8.

Timeline

1. 25-08-2026
   PublishedVulnerability first disclosed.
2. 25-08-2026
   Last modifiedVulnerability information updated.

Description

The tagDiv Composer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the vc_raw_html shortcode in all versions up to and including 5.4.5. This is due to insufficient input sanitization and output escaping in the vc_raw_html::render() method, which base64-decodes shortcode content (after a strip_tags() that is bypassed because the encoded payload contains no tags on save) and concatenates the result directly into the page HTML. Because WordPress's save-time wp_kses_post() filter only sees the inert base64 text inside a normal shortcode bracket and does not decode it, the dangerous tags survive into post_content and are emitted unescaped at render time. 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 (for example, when an Editor or Administrator previews the pending post).

• 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.