CVE-2026-75962
Post SMTP <= 4.0.1 - Unauthenticated Stored DOM-Based Cross-Site Scripting via 'user_email' Parameter (Multisite Registration → Failed Email Log)
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 'user_email' parameter in all versions up to, and including, 4.0.1 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. This is exploitable without authentication on WordPress Multisite installations with public registration enabled, as WordPress accepts email addresses containing numeric HTML character references that Post SMTP's stricter validator rejects, persisting the attacker-controlled address verbatim to the email log via the failed-send exception message.
INFO
Published Date :
Oct. 6, 2026, 6:17 a.m.
Last Modified :
Oct. 6, 2026, 6:17 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-75962
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update the Post SMTP plugin to version 4.0.2.
- Sanitize and escape user input for email parameters.
- Restrict public registration if not needed.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-75962.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-75962 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-75962
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-75962 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-75962 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Oct. 06, 2026
Action Type Old Value New Value Added 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 'user_email' parameter in all versions up to, and including, 4.0.1 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. This is exploitable without authentication on WordPress Multisite installations with public registration enabled, as WordPress accepts email addresses containing numeric HTML character references that Post SMTP's stricter validator rejects, persisting the attacker-controlled address verbatim to the email log via the failed-send exception message. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N Added CWE CWE-79 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/75xxx/CVE-2026-75962.json">CVE-2026-75962</a> Added Reference https://plugins.trac.wordpress.org/browser/post-smtp/tags/3.9.5/Postman/Postman-Email-Log/PostmanEmailLogService.php#L215 Added Reference https://plugins.trac.wordpress.org/browser/post-smtp/tags/3.9.5/Postman/Postman-Mail/PostmanEmailAddress.php#L63 Added Reference https://plugins.trac.wordpress.org/browser/post-smtp/tags/3.9.5/Postman/PostmanEmailLogs.php#L538 Added Reference https://plugins.trac.wordpress.org/browser/post-smtp/tags/3.9.5/Postman/PostmanWpMail.php#L374 Added Reference https://plugins.trac.wordpress.org/browser/post-smtp/tags/3.9.5/script/postman-email-logs.js#L711 Added Reference https://plugins.trac.wordpress.org/changeset/3711068/post-smtp/trunk/Postman/Postman-Email-Log/PostmanEmailLogService.php Added Reference https://plugins.trac.wordpress.org/changeset?reponame=&new=3711079%40post-smtp%2Ftags%2F4.0.2&old=3664536%40post-smtp%2Ftags%2F4.0.1 Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/accac3da-0318-4e79-a163-ed9ff2af692b?source=cve