CVE-2025-4172 is a stored cross-site scripting vulnerability in the VerticalResponse Newsletter Widget WordPress plugin by katzwebdesign. It affects all versions up to 1.6 due to improper neutralization of input during web page generation (CWE-79). Authenticated attackers with contributor-level privileges or above can exploit this by injecting malicious scripts via the 'verticalresponse' shortcode attributes, which are not properly sanitized or escaped. These scripts execute in the context of any user viewing the injected page, potentially leading to session hijacking or other script-based attacks. The CVSS 3.1 base score is 6.4, reflecting a network attack vector with low attack complexity, requiring privileges, no user interaction, and impacting confidentiality and integrity with no availability impact.

An attacker with contributor-level or higher access can inject persistent malicious scripts into pages using the vulnerable shortcode. This can lead to unauthorized script execution in the browsers of users who view the affected pages, potentially compromising user sessions or data confidentiality and integrity. There is no indication of availability impact. No known exploits in the wild have been reported.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict contributor-level access to trusted users only and consider disabling or removing the VerticalResponse Newsletter Widget plugin if feasible to prevent exploitation.