CVE-2025-13516 File upload in SureMail – SMTP and Email Logs Plugin with Amazon SES, Postmark, and Other Providers
Unauthenticated attackers can upload malicious PHP files via email attachments to achieve remote code execution on sites using non-Apache or misconfigured web servers.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-13516?
CVE-2025-13516 is a high-severity vulnerability in brainstormforce SureMail – SMTP and Email Logs Plugin with Amazon SES, Postmark, and Other Providers, published on 2 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The SureMail – SMTP and Email Logs Plugin for WordPress is vulnerable to Unrestricted Upload of File with Dangerous Type in versions up to and including 1.9.0. This is due to the plugin's save_file() function in inc/emails/handler/uploads.php which duplicates all email attachments to a web-accessible directory (wp-content/uploads/suremails/attachments/) without validating file extensions or content types. Files are saved with predictable names derived from MD5 hashes of their content. While the plugin attempts to protect this directory with an Apache .htaccess file to disable PHP execution, this protection is ineffective on nginx, IIS, and Lighttpd servers, or on misconfigured Apache installations. This makes it possible for unauthenticated attackers to achieve Remote Code Execution by uploading malicious PHP files through any public form that emails attachments, calculating the predictable filename, and directly accessing the file to execute arbitrary code granted they are exploiting a site running on an affected web server configuration.
Weakness: CWE-434
Which versions are affected by CVE-2025-13516?
How do I fix CVE-2025-13516?
No fix has been published for CVE-2025-13516 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-13516 being exploited?
There is no known exploitation of CVE-2025-13516 in the wild and no public exploit code.
Sources
Also known as GHSA-cmg2-755q-2pj5.