Post SMTP Mailer/Email Log <= 2.1.3 - Authenticated (Admin+) Stored Cross-Site Scripting
Strategic Overview
- Status
- Patched in 2.1.4
- Affected Plugin
- Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App
- Affected Version
<= 2.1.3- CVSS
- 5.5Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CVE
CVE-2022-2351
At a glance
CVE-2022-2351 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Post SMTP WordPress plugin, affecting versions <= 2.1.3. It carries a CVSS score of 5.5 (reachable over the network; low attack complexity). Exploitation requires an authenticated account at Admin level or above. The issue is fixed in version 2.1.4; sites on affected versions should update now. Disclosed August 2022.
Vulnerability Overview
The Post SMTP Mailer/Email Log plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘input_tmp_dir’ parameter in versions up to, and including, 2.1.3 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user.
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Post SMTP <= 2.1.3 carries this weakness at input_tmp_dir, and reaching it takes an account at Admin level or above. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.
Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For Post SMTP the fix is 2.1.4: builds <= 2.1.3 are affected, anything from 2.1.4 onward is not.
Remediation
Update to version 2.1.4, or a newer patched version
How does WordSec protect against this?
An attacker needs Admin access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Post SMTP 2.1.4 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
Related records
Same weakness class
Other vulnerabilities in Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App
- 9.8CVE-2025-11833: Post SMTP Account Takeover
CVE-2025-11833 - 9.8CVE-2023-6875: POST SMTP Mailer Authorization Bypass
CVE-2023-6875 - 8.8CVE-2025-24000: Post SMTP Authenticated (Subscriber+) Account Takeover
CVE-2025-24000 - 7.2CVE-2024-5207: POST SMTP Mailer SQL Injection
CVE-2024-5207 - 7.2CVE-2023-6620: POST SMTP Mailer SQL Injection
CVE-2023-6620 - 7.2CVE-2023-5958: POST SMTP Mailer <= 2.7.0 Stored Cross-Site Scripting
CVE-2023-5958 - 7.2Post SMTP <= 2.6.0 SQL Injection
- 7.2CVE-2023-3082: Post SMTP <= 2.5.7 Stored Cross-Site Scripting
CVE-2023-3082
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