Cyber Resilience

CVE-2025-3643

Medium

Published: 25 April 2025

Published
25 April 2025
Modified
24 June 2025
KEV Added
—
Patch
—
CVSS Score v3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0013 32.1th percentile
Risk Priority 11 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-3643 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Moodle Moodle. Its CVSS base score is 5.4 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 32.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

A flaw was found in Moodle. The return URL in the policy tool required additional sanitizing to prevent a reflected Cross-site scripting (XSS) risk.

CWE(s)
CWE-79

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 →
T1059.007 JavaScript Execution
Adversaries may abuse various implementations of JavaScript for execution.
attack.mitre.org →
T1056 Input Capture Collection
Adversaries may use methods of capturing user input to obtain credentials or collect information.
attack.mitre.org →
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
attack.mitre.org →
T1555.003 Credentials from Web Browsers Credential Access
Adversaries may acquire credentials from web browsers by reading files specific to the target browser.
attack.mitre.org →
Why these techniques?

Reflected XSS in Moodle's policy tool allows arbitrary JavaScript execution in victims' browsers via crafted return URLs, enabling exploitation of public-facing applications (T1190), JavaScript command execution (T1059.007), input capture (T1056), web session cookie theft (T1539), and browser credential theft (T1555.003).

Affected Assets

moodle
moodle
≤ 4.1.18 · 4.3.0 — 4.3.12 · 4.4.0 — 4.4.8

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.

CA-8 Penetration Testing
addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

SI-10 Information Input Validation
addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

SI-15 Information Output Filtering
addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References