VulnCrest
Search
Create account
Report an incident
Radar sectionsDatabase
Check my site
WordPress plugin

POST SMTP Mailer <= 2.0.20 — Cross-Site Request Forgery Bypass

CVE-2021-4422Published · Updated

Action summary

Affected: ≤2.0.20Update to 2.0.21 or newer

All remediation steps
Watch plugin
Severity
Medium4.3
CVSS
4.3
CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
What does this vector mean?
AV:N Attack vector
Network
AC:L Attack complexity
Low
PR:N Privileges required
None
UI:R User interaction
Required
S:U Scope
Unchanged
C:N Confidentiality
None
I:L Integrity
Low
A:N Availability
None
Weakness
CWE-352 CSRF
Required access
No account needed
Exploit prediction (EPSS)
No score
CISA KEV
Not listed
On this page8

Am I affected?

Post SMTP – Complete Email Delivery and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App post-smtp

  1. Affected≤ 2.0.20
  2. Patched in2.0.21

Update to 2.0.21 or newer.

You are affected if you run ≤ 2.0.20. Version 2.0.21 and later are not affected by this issue.

  • Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Post SMTP – Complete Email Delivery and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App.
  • No admin access? Run a passive check of your site. It reads public files only.
  • No account is needed to exploit this. Treat any exposed site on an affected version as at risk.

What to do

  1. Update to version 2.0.21, or a newer patched version
  2. Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
  3. Watch Post SMTP – Complete Email Delivery and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App to get an email when the next vulnerability is published.

Advisory

Source description from Wordfence Intelligence, credited to Jerome Bruandet.

The POST SMTP Mailer plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 2.0.20. This is due to missing or incorrect nonce validation on the handleCsvExport() function. This makes it possible for unauthenticated attackers to trigger a CSV export via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

Exploits & references

Proof-of-concept & detection

No public proof-of-concept or detection template is known for this vulnerability.

Advisories & patches

More in Post SMTP – Complete Email Delivery and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App

All 28
More vulnerabilities in Post SMTP – Complete Email Delivery and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App
SeverityVulnerabilityCVEPublished
High7.2Unauthenticated Stored DOM-Based Cross-Site Scripting via 'user_email' Parameter (Multisite Registration → Failed Email Log)
≤4.0.1Update to 4.0.2
CVE-2026-75962
Medium6.3Missing Authorization to Authenticated (Subscriber+) Settings Change
4.0.0-beta.1 – 4.0.0-beta.1Update to 4.0.1
CVE-2026-81278
High7.2Unauthenticated Stored Cross-Site Scripting
≤3.6.2Update to 3.6.3
CVE-2026-48838
Medium6.1Reflected DOM-Based Cross-Site Scripting via url Parameter
≤5.5.8Update to 5.5.9
CVE-2024-13362
High7.2Unauthenticated Stored Cross-Site Scripting via 'event_type'
≤3.8.0Update to 3.9.0
CVE-2026-3090

Same weakness (CSRF)

All CSRF
Other CSRF vulnerabilities
SeverityVulnerabilityCVEPublished
High7.2Unauthenticated Stored Cross-Site Scripting via Comment User-Agent Header
EZ SQL Reports Shortcode Widget and DB Backup≤5.25.25Update to 5.26.45
CVE-2026-120688
Critical9.8Unauthenticated Arbitrary File Upload via File Upload via Public Form Submission
Chatterbug Forms – Fast, Flexible WordPress Form Builder≤1.0.2Update to 1.1
CVE-2026-125055
Critical9.8Unauthenticated PHP Object Injection to Remote Code Execution via 'form' Parameter
ELEX WordPress HelpDesk & Customer Ticketing System≤3.3.9Update to 3.4.0
CVE-2026-119077
Medium5.3Unauthenticated Sensitive Information Exposure in 'search' Parameter
Customer Reviews for WooCommerce≤5.127.0Update to 5.128.0
CVE-2026-121518

Timeline

  1. CVE published

    Severity medium, CVSS 4.3

  2. Record last updated

Sources & licenses

Wordfence record
Vulnerability data
Wordfence Intelligence. [object Object] Licensed under the CC BY-SA 4.0.
CVE® identifiers
[object Object]. Used under the CVE Program. CVE® is a registered trademark of The MITRE Corporation.
CVSS / CWE
National Vulnerability Database (NVD), shown unmodified. This product uses the NVD API but is not endorsed or certified by the NVD.
VulnCrest content
Summary, remediation guidance and page layout © VulnCrest. Not sourced from NVD.

How we use these sources

Search VulnCrest Radar

Jump to

Are you sure?