CVE-2026-4080 is a stored cross-site scripting vulnerability in the Easy Cart WordPress plugin caused by improper neutralization of input during web page generation (CWE-79). The vulnerability arises because the ectp_add_to_cart() function sanitizes user-supplied shortcode attributes using sanitize_text_field(), which removes HTML tags but does not escape double quotes. This allows an attacker with Contributor-level privileges or higher to inject arbitrary JavaScript by breaking out of HTML attribute contexts in the 'add_to_cart' shortcode. The injected scripts execute in the context of any user visiting the compromised page, potentially leading to session hijacking or other script-based attacks. The CVSS 3.1 base score is 6.4 (medium severity), with network attack vector, low attack complexity, requiring privileges, no user interaction, and partial impact on confidentiality and integrity.

An authenticated attacker with Contributor-level access or higher can inject persistent malicious scripts into pages using the vulnerable shortcode. These scripts execute in the browsers of users who visit the affected pages, potentially compromising user sessions or performing unauthorized actions within the context of the victim's browser. The impact is limited to confidentiality and integrity with no availability impact. There is no indication of known exploits in the wild at this time.

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 Easy Cart plugin if possible. Avoid using the 'add_to_cart' shortcode with untrusted input. Monitor for vendor updates regarding patches or official mitigations.