CVE-2026-2840 is a stored cross-site scripting vulnerability in the Email Encoder – Protect Email Addresses and Phone Numbers WordPress plugin, affecting all versions up to 2.4.4. The vulnerability is triggered via the 'eeb_mailto' shortcode, which does not properly sanitize or escape input, allowing authenticated users with contributor-level access or higher to inject arbitrary JavaScript code. This code executes in the context of users who view the compromised pages, potentially leading to session hijacking or other script-based attacks. The CVSS 3.1 vector indicates network attack vector, low attack complexity, privileges required at low level, no user interaction, and impacts confidentiality and integrity with no impact on availability.

An attacker with contributor or higher privileges can inject persistent malicious scripts into pages using the vulnerable shortcode. This can lead to unauthorized actions performed in the context of other users viewing the injected content, potentially compromising user confidentiality and integrity. There is no impact on system availability. No known exploits have been reported in the wild.

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 vulnerable plugin if possible. Monitor for plugin updates from the vendor that address this vulnerability.