CVE-2025-4220 is a stored cross-site scripting vulnerability in the Xavin's List Subpages WordPress plugin, affecting all versions up to and including 1.3. The issue arises from improper neutralization of input in the 'xls' shortcode, allowing authenticated users with contributor or higher privileges to inject arbitrary web scripts. These scripts execute in the context of any user who accesses the injected page, potentially leading to session hijacking or other script-based attacks. The vulnerability has a CVSS 3.1 score of 6.4 (AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N), reflecting network attack vector, low attack complexity, and partial confidentiality and integrity impact. No patch or remediation details are currently provided by the vendor or other authoritative sources.

An attacker with contributor-level or higher access can inject persistent malicious scripts into pages via the vulnerable shortcode. These scripts execute in the browsers of users who visit the compromised pages, potentially allowing theft of user credentials, session tokens, or other sensitive information. The vulnerability does not affect availability. The impact is limited by the requirement for authenticated access with contributor privileges or above.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict contributor-level access to trusted users only and consider disabling or removing the Xavin's List Subpages plugin if feasible. Monitor for updates from the vendor or WordPress plugin repository regarding patches or mitigations.