Medium severity · published Oct 1, 2026
CVE-2026-89427
Ad Inserter <= 2.8.18 - Reflected Cross-Site Scripting via 's' Search Parameter
6.1
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 17% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AI
Ad Inserter – Ad Manager & AdSense Ads · spacetime
through 2.8.18 · source: vendor
Affected product
AI
Ad Inserter – Ad Manager & AdSense Ads
spacetime
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89427
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-89427
www.wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/c01f98a4-c349-4cb2-b09a-5cbadfcad830?source=cve
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/ad-inserter/tags/2.8.18/ad-inserter.php#L13081
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/ad-inserter/tags/2.8.18/ad-inserter.php#L13012
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/ad-inserter/tags/2.8.18/ad-inserter.php#L12903
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/changeset?reponame=&new=3709970%40ad-inserter%2Ftags%2F2.8.19&old=3624916%40ad-inserter%2Ftags%2F2.8.18
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/changeset/3709957/ad-inserter/trunk/ad-inserter.php
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