CVE-2026-19902 · AETERNAE Research

Disclosure summary

The Ad Inserter – Ad Manager & AdSense Ads plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the Referer header in all versions up to, and including, 2.8.18 due to insufficient input sanitization and output escaping on the '{search-query}' dynamic tag. When an ad block's code contains that tag, replace_ai_tags() reads $_SERVER['HTTP_REFERER'] and tests it with the regex /[\.\/](google|yahoo|bing|ask)\.[a-z\.]{2,5}[\/]/i. The leading [\.\/] class matches a literal slash, so any referrer merely containing a segment such as '/google.com/' passes as a search-engine referral; the plugin then percent-decodes the referring query with parse_str() and substitutes the resulting 'q' (or 'p') value into the block via preg_replace() with no escaping. This makes it possible for unauthenticated attackers to execute arbitrary JavaScript in the context of the site for any visitor, including a signed-in administrator, by luring them to an attacker-controlled page that frames or links to any ordinary post. Exploitation requires the site to have an ad block whose code uses the '{search-query}' tag with automatic insertion enabled — a documented plugin feature used as intended.

Source-reported weakness categories

CWE-79

Source-specific records & product guidance

Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.

NIST National Vulnerability Database · NVD-CVE-2026-19902

Open original source · Updated Oct 03, 2026

Only CPE matches marked vulnerable=true are indexed. AND/OR platform conditions must be checked in the original NVD record.

Original records & references

PUBLISHED 2026-10-01T04:16:51-04:00
MODIFIED 2026-10-03T12:16:36-04:00
INGESTED 2026-10-06T11:45:14-04:00

CVE-2026-19902.

Disclosure summary

Source-reported weakness categories

Source-specific records & product guidance

Original records & references