High severity · published Mar 18, 2026
CVE-2026-3090
Post SMTP <= 3.8.0 - Unauthenticated Stored Cross-Site Scripting via 'event_type'
7.2
CVSS
0.2%
EPSS
No
On KEV
Description
The Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘event_type’ parameter in all versions up to, and including, 3.8.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The vulnerability is only exploitable when the Post SMTP Pro plugin is also installed and its Reporting and Tracking extension is enabled.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PS
Affected product
PS
Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App
saadiqbal
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-3090
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-3090
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/post-smtp/trunk/Postman/PostmanEmailLogs.php#L459
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/changeset/3484515/
www.wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/3f8cbbbb-2089-4966-8fd3-da4f76fb2517?source=cve
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