CVE intelligence and bounded remediation

CVE-2026-11900 — Ad Inserter security vulnerability

Medium CVSS 4.3

The Ad Inserter – Ad Manager & AdSense Ads plugin for WordPress is vulnerable to Insecure Direct Object Reference in versions up to and including 2.8.16 via the 'data' attribute of the [adinserter] shortcode. This is due to the replace_ai_tags() function processing a {reusable-block-N} tag pattern that calls get_post_field('post_content', N) without verifying the requesting user's capability with current_user_can('read_post'), without restricting the post type to 'wp_block', and without checking the post status. This makes it possible for authenticated attackers, with Contributor-level access and above, to read the full content of arbitrary posts including Private, Draft, Pending, Trashed, and password-protected posts owned by other users, by placing the shortcode in a post they own and previewing it.

Severity
Medium
CVSS
4.3 (3.1)
Published
2026-07-03
CISA KEV
Not currently listed
Ecosystem
php/wordpress
Weaknesses
CWE-639

Affected products

No browser-safe affected-product rows are available.

Matched remediation archetype

Authorization bypass, IDOR, and cross-tenant access

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Map object and action authorization checks across API, UI, batch, import/export, and background-job paths.
  • Identify tenant, ownership, role, and policy boundaries for affected resources and administrative operations.
  • Use synthetic fixtures to compare intended access matrices without accessing another user's real data.

Remediate safely

  • Enforce server-side authorization at each resource access and state transition using the authenticated principal and trusted tenant context.
  • Scope data queries by tenant and ownership; treat client-supplied identifiers, roles, and policy claims as untrusted.
  • Add deny-by-default policy tests for horizontal and vertical access across every affected transport.

Authoritative sources

Complete CVE record and remediation plan

The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.