CVE-2025-67849: Moodle: moodle: cross-site scripting (xss) via improper sanitization of ai prompt responses

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-03 · updated 2026-06-17
Weakness: CWE-79

Description

A flaw was found in Moodle. This cross-site scripting (XSS) vulnerability, caused by improper sanitization of AI prompt responses, allows attackers to inject malicious HTML or script into web pages. When other users view these compromised pages, their sessions could be stolen, or the user interface could be manipulated.

Affected products

Moodle: from 4.5.0 before 4.5.8; from 5.0.0 before 5.0.4; 5.1.0 — fixed in 4.5.8, 5.0.4

How to fix

Upgrade to a fixed version: Moodle 4.5.8, 5.0.4. Check the vendor advisory for mitigations.

References

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