CVE-2025-11833 Scanner

Post SMTP is a popular WordPress plugin used primarily to enhance email functionalities by providing a complete SMTP solution including logs, alerts, and a backup SMTP. This plugin is extensively utilized by WordPress site owners who seek increased reliability and control over their email handling processes. It serves to optimize email deliverability, integrating seamlessly with a wide array of email providers, and supplying detailed logs to track email issues. Administrators of WordPress websites deploy Post SMTP to ensure consistent delivery of emails such as contact form entries, notifications, and password resets. It aids in configuring email authentication mechanisms, including SPF and DKIM, to prevent emails from landing in spam folders. Due to its extensive email diagnostic capabilities, it is favored by tech-savvy WordPress users who require advanced solutions for their email sending needs.

The configuration file disclosure vulnerability in Post SMTP WordPress plugin occurs due to an unauthorized access flaw that lets unauthenticated attackers access and read logged emails. By exploiting this missing capability check in the `__construct` function, attackers can stealthily gather sensitive data by retrieving email logs. As these emails can contain critical information such as password reset links, the vulnerability poses a severe security risk. This absence of constraint allows attackers to potentially escalate their privileges or compromise user accounts. Exploiting this vulnerability requires no prior authentication, making it a high-severity concern for websites using affected versions of the plugin.

The configuration file disclosure vulnerability is communicated through a specific endpoint, where attackers can send crafted requests to access email logs without needing authentication. The vulnerability lies in the lack of control over access permissions in the `__construct` function, where important authorization checks are skipped. Attackers make use of known endpoints to fetch sensitive data if the logs are exposed. The vulnerable parameter in play is the log retrieval functionality, which fails to enforce access restrictions on unauthenticated users. This oversight enables hostile actions where the attacker simulates a legitimate request to harvest sensitive logs by exploiting the vulnerable system's internal functions.

If exploited, this vulnerability could lead to severe repercussions including unauthorized access to sensitive user data, the potential for account hijacking, and broader security breaches. Malicious actors can leverage the information obtained from email logs to reset passwords, potentially taking over user accounts. Particularly, any exposed password reset links within the logs can allow attackers to change user passwords without consent. Consequently, such unauthorized access might also enable attackers to infiltrate further into the application or connected systems. Other potential effects include the exploitation of disclosed information to conduct phishing attacks or other forms of social engineering, leading to broader organizational risk.

REFERENCES

• https://github.com/Kazgangap/cve-poc-garage/blob/main/2025/CVE-2025-11833.md
• https://www.wordfence.com/threat-intel/vulnerabilities/wordpress-plugins/post-smtp/post-smtp-complete-smtp-solution-with-logs-alerts-backup-smtp-mobile-app-360-missing-authorization-to-account-takeover-via-unauthenticated-email-log-disclosure
• https://nvd.nist.gov/vuln/detail/CVE-2025-11833