The AMP for WP plugin has a flaw that allows attackers who do not need to authenticate to permanently store malicious JavaScript code through the comment submission interface. The vulnerability arises from a regex transformation that fails to escape or block javascript: URIs during save and output filtering, giving the injected script a path to execute whenever a mitigated AMP page is rendered. Successful exploitation can lead to arbitrary script execution, enabling phishing, session hijacking, data theft, or defacement when visitors view affected pages.

WordPress sites using the AMP for WP – Accelerated Mobile Pages plugin, versions 1.1.16 or earlier, are vulnerable. Upgrade to a newer, un‑vulnerable release to remove the risk.

The vulnerability carries a CVSS score of 7.2, indicating high severity. No EPSS score is available, and the issue is not listed in CISA’s KEV catalog, so the precise likelihood of exploitation is unclear. The attack vector requires submitting a comment to a site that accepts user input; once stored in the database the malicious script will run for any visitor to the impacted page, giving the attacker broad impact on all site users. Because the condition does not require authentication, the barrier to attack is low and many sites may be exposed.