CVE-2025-13516: SureMail – SMTP and Email Logs Plugin with Amazon SES, Postmark, and Other Providers <= 1.9.0 - Unauthenticated Arbitrary File Upload

Is it exploited?

Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of 10 Nov 2026.

VulnCheck KEV lists it since 11 Nov 2026. It cites 1 public report, the first from 11 Nov 2026.

• patchstack.com

How likely is exploitation in the next 30 days?

1%

EPSS score, percentile 64.4 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?

8.1 High

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

No patch or vendor advisory is listed in the CVE record. Check Brainstorm Force's advisories.

Which versions are affected?

Affected

• 1.9.0 and earlier

Versions by product

Source: CISA KEV 2026.11.10, as of 10 Nov 2026; VulnCheck KEV, as of 12 Nov 2026; FIRST EPSS, as of 12 Nov 2026; CVE List, as of 12 Nov 2026. About the data.

Description

SureMail – SMTP and Email Logs Plugin with Amazon SES, Postmark, and Other Providers <= 1.9.0 - Unauthenticated Arbitrary File Upload

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.

Source: CVE List, as of 12 Nov 2026. About the data.

What to do

Advisories and patches

No patch, vendor advisory or mitigation is listed in the CVE record. Check Brainstorm Force's own security advisories for a fix, and compare your version with the affected versions below.

This summary is based on the CVE record as of 12 Nov 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

Source: CVE List, as of 12 Nov 2026. About the data.

Timeline