Cyber Resilience

CVE-2025-23703

High

Published: 16 January 2025

Published
16 January 2025
Modified
23 April 2026
KEV Added
—
Patch
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CVSS Score v3.1 7.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
EPSS Score 0.0017 38.0th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-23703 is a high-severity CSRF (CWE-352) vulnerability. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 38.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SC-23 (Session Authenticity) and SI-10 (Information Input Validation).

Deeper analysis

CVE-2025-23703 is a Cross-Site Request Forgery (CSRF) vulnerability in the Free MailClient FMC WordPress plugin by cstoltenkamp that allows Stored XSS. The issue affects the plugin from unknown initial versions through 1.0 inclusive, as documented under CWE-352.

The vulnerability carries a CVSS v3.1 base score of 7.1 (AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L), indicating exploitation over the network with low complexity, no required privileges, and user interaction. An unauthenticated attacker can trick an authenticated user into submitting a malicious request via a crafted webpage, resulting in the storage of XSS payloads that execute with changed scope and low impacts on confidentiality, integrity, and availability.

Mitigation details are available in the Patchstack advisory at https://patchstack.com/database/Wordpress/Plugin/mailclient/vulnerability/wordpress-free-mailclient-fmc-plugin-1-0-csrf-to-stored-xss-vulnerability?_s_id=cve.

EU & UK References

Vulnerability details

Cross-Site Request Forgery (CSRF) vulnerability in cstoltenkamp Free MailClient FMC mailclient allows Stored XSS.This issue affects Free MailClient FMC: from n/a through <= 1.0.

CWE(s)
CWE-352

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Why these techniques?

The CSRF-to-stored-XSS vulnerability in a public-facing WordPress plugin directly enables exploitation of the application over the network (T1190).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

CVEs Like This One

CVE-2024-37102Shared CWE-352
CVE-2024-37450Shared CWE-352
CVE-2025-23558Shared CWE-352
CVE-2025-68722Shared CWE-352
CVE-2025-31440Shared CWE-352
CVE-2025-23848Shared CWE-352
CVE-2025-22571Shared CWE-352
CVE-2024-53684Shared CWE-352
CVE-2025-23455Shared CWE-352
CVE-2025-22582Shared CWE-352

Affected Assets

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SI-2 Flaw Remediation good match
prevent

SI-2 requires identification, reporting, and correction of the specific CSRF to stored XSS flaw in the FMC WordPress plugin, directly eliminating the vulnerability.

SC-23 Session Authenticity good match
prevent

SC-23 enforces session authenticity mechanisms such as anti-CSRF tokens, preventing unauthenticated attackers from forging requests to store XSS payloads.

SI-10 Information Input Validation good match
prevent

SI-10 validates information inputs to reject or sanitize malicious XSS payloads that could be stored via the CSRF vulnerability.

References