Cyber Resilience

CVE-2021-4422

Medium

Published: 12 July 2023

Published
12 July 2023
Modified
08 April 2026
KEV Added
Patch
CVSS Score v3.1 4.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
EPSS Score 0.0031 54.9th percentile
Risk Priority 9 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-4422 is a medium-severity CSRF (CWE-352) vulnerability in Wpexperts Post Smtp. Its CVSS base score is 4.3 (Medium).

Operationally, ranked in the top 45.1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

wpexperts
post smtp
≤ 2.0.20

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-352

Awareness training educates users on avoiding untrusted links and actions that can be exploited via CSRF.

addresses: CWE-352

Requiring user re-entry of credentials for sensitive actions prevents automated forgery of requests without active user participation.

addresses: CWE-352

Security testing regimens explicitly include checks for missing or ineffective anti-CSRF protections in web applications.

addresses: CWE-352

Detects anomalous request patterns consistent with cross-site request forgery.

References