CVE-2025-11833 is a critical security vulnerability identified in the Post SMTP – Complete SMTP Solution with Logs, Alerts, Backup SMTP & Mobile App WordPress plugin, developed by saadiqbal. The vulnerability arises from a missing authorization check (CWE-862) in the __construct function of the plugin in all versions up to and including 3.6.0. This flaw allows unauthenticated attackers to bypass capability checks and access the email logs maintained by the plugin. Since these logs can contain sensitive information such as password reset emails and their associated reset links, an attacker can leverage this access to hijack user accounts by initiating password resets and intercepting the reset links. The vulnerability is remotely exploitable without any authentication or user interaction, making it highly accessible to attackers. The CVSS v3.1 base score of 9.8 reflects the critical nature of this flaw, with high impact on confidentiality, integrity, and availability. Although no known exploits are currently reported in the wild, the ease of exploitation and the sensitive nature of the data exposed make this a severe threat. The plugin is widely used in WordPress environments to manage SMTP email sending, logging, and alerts, making the attack surface significant. The lack of a patch at the time of reporting necessitates immediate risk mitigation steps to prevent potential exploitation.

For European organizations, this vulnerability poses a significant risk of unauthorized data disclosure and account takeover. Organizations relying on the Post SMTP plugin for email delivery and logging may have sensitive information exposed, including password reset emails that can be used to compromise user accounts. This can lead to unauthorized access to corporate resources, data breaches, and potential lateral movement within networks. The confidentiality of user credentials and internal communications is at risk, which can damage organizational reputation and lead to regulatory non-compliance, especially under GDPR. The integrity and availability of email services may also be impacted if attackers manipulate or disrupt email logs and alerts. Given the critical severity and ease of exploitation, European entities with public-facing WordPress sites using this plugin are particularly vulnerable to targeted attacks or opportunistic exploitation by cybercriminals.

1. Immediately monitor for updates from the plugin developer and apply patches as soon as they become available. 2. Until a patch is released, restrict access to the WordPress admin dashboard and specifically to the Post SMTP plugin’s email logs by implementing strict role-based access controls and IP whitelisting. 3. Disable or remove the Post SMTP plugin if it is not essential, or replace it with alternative SMTP plugins that have verified security controls. 4. Conduct an audit of email logs and user accounts to detect any suspicious activity or unauthorized access attempts. 5. Implement multi-factor authentication (MFA) on WordPress admin accounts to reduce the risk of account takeover. 6. Regularly review and harden WordPress security configurations, including limiting plugin installations and updates to trusted administrators. 7. Educate users about phishing risks related to password reset emails and encourage prompt reporting of suspicious emails. 8. Employ web application firewalls (WAFs) to detect and block exploitation attempts targeting this vulnerability. 9. Monitor network traffic for unusual access patterns to the WordPress backend or SMTP logs. 10. Prepare incident response plans to quickly address any detected exploitation or data breaches related to this vulnerability.