CVE-2026-89427 Ad Inserter <= 2.8.18 - Reflected Cross-Site Scripting via 's' Search Parameter
Unauthenticated attackers can inject arbitrary scripts via the search parameter if specific placeholders are enabled, requiring user interaction to execute.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-89427?
CVE-2026-89427 is a medium-severity cross-site scripting vulnerability in spacetime Ad Inserter – Ad Manager & AdSense Ads, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The Ad Inserter – Ad Manager & AdSense Ads plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via 's' Search Parameter in all versions up to, and including, 2.8.18 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. Exploitation requires that a site administrator has configured at least one Ad Inserter block using the {title} or {short-title} placeholder with that block enabled for search pages, which is a standard, documented plugin feature.
Weakness: CWE-79
Which versions are affected by CVE-2026-89427?
How do I fix CVE-2026-89427?
No fix has been published for CVE-2026-89427 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-89427 being exploited?
There is no known exploitation of CVE-2026-89427 in the wild and no public exploit code.
Sources
Also known as GHSA-cjx2-r3r5-6cq4.