CVE-2026-11983

Ad Inserter <= 2.8.16 - Missing Authorization to Block Visibility Bypass via ai_ajax

2026-08-05 22:18

Strategic Overview

Status: Patched in 2.8.17
Affected Plugin: Ad Inserter – Ad Manager & AdSense Ads
Affected Version: <= 2.8.16
CVSS: 5.3Medium
Weakness type: CWE-862 · Missing Authorization
CVE: CVE-2026-11983

View all Ad Inserter – Ad Manager & AdSense Ads vulnerabilities

At a glance

CVE-2026-11983 is a medium-severity Missing Authorization vulnerability in the Ad Inserter WordPress plugin, affecting versions <= 2.8.16. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 2.8.17; sites on affected versions should update now. Disclosed August 2026, reported by AlexHenry.

Vulnerability Overview

The Ad Inserter – Ad Manager & AdSense Ads plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 2.8.16 due to a missing capability check in the `ai_ajax` function. This makes it possible for unauthenticated attackers to view the contents of ad blocks that an administrator has restricted to administrator-only visibility.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-862: Missing Authorization

Reaching this weakness in Ad Inserter <= 2.8.16 takes a caller who can reach the endpoint. A missing authorization check means a function is reachable by anyone who can reach the endpoint, because the code never asks whether the caller is allowed to perform the action.

Any user who can reach the endpoint gets to run an action reserved for higher-privileged roles, from reading protected data to changing settings or content. For Ad Inserter the fix is 2.8.17: builds <= 2.8.16 are affected, anything from 2.8.17 onward is not.

Remediation

Update to version 2.8.17, or a newer patched version

How WordSec helps

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: Ad Inserter 2.8.17 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-11983 https://www.wordfence.com/threat-intel/vulnerabilities/id/b5715acd-62e6-4cd8-8fe8-4b1412f287c9 https://nvd.nist.gov/vuln/detail/CVE-2026-11983

Related records

Same weakness class

Other vulnerabilities in Ad Inserter – Ad Manager & AdSense Ads

CVSS Vector

5.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityLow
IntegrityNone
AvailabilityNone

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