CVE-2026-28177 is an unauthenticated cross-site scripting (XSS) vulnerability in Daniel Iser's Popup Maker plugin, affecting all versions up to 1.23.0. The vulnerability arises from improper neutralization of input during web page generation (CWE-79), allowing attackers to inject malicious scripts that execute in the context of the victim's browser. The CVSS 3.1 base score is 7.1, reflecting network attack vector, low attack complexity, no privileges required, user interaction required, and impacts on confidentiality, integrity, and availability. No official patch or remediation level is currently documented, and no known exploits are reported in the wild.

Successful exploitation of this vulnerability can lead to execution of arbitrary scripts in the context of the affected web application, potentially resulting in data theft, session hijacking, or other malicious actions impacting confidentiality, integrity, and availability. Since the vulnerability is unauthenticated and remotely exploitable, it poses a significant risk to users of affected versions.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, users should consider implementing input validation and output encoding as temporary mitigations to reduce risk. Monitoring for updates from the vendor Daniel Iser is recommended.