Medium severity · published Jul 12, 2023
CVE-2021-4422
POST SMTP Mailer <= 2.0.20 - Cross-Site Request Forgery Bypass
4.3
CVSS
0.5%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 45% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PS
Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App · saadiqbal
through 2.0.20 · source: vendor
PS
Post Smtp · Wpexperts
through 2.0.20 · source: NVD
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-2021-4422
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-4422
Third Party Advisory
https://blog.nintechnet.com/25-wordpress-plugins-vulnerable-to-csrf-attacks/
Third Party Advisory
https://blog.nintechnet.com/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/
Third Party Advisory
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/
Third Party Advisory
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-2/
Third Party Advisory
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-3/
Third Party Advisory
https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-4/
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