CVE-2023-23922: Moodle: reflected xss risk in blog search

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-02-17 · updated 2026-06-17
Weakness: CWE-79

Description

The vulnerability was found Moodle which exists due to insufficient sanitization of user-supplied data in blog search. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website. This flaw allows a remote attacker to perform cross-site scripting (XSS) attacks.

Affected products

Moodle: from 4.0.0 before 4.0.6; 4.1.0 — fixed in 4.0.6

How to fix

Upgrade to a fixed version: Moodle 4.0.6. Check the vendor advisory for mitigations.

References

http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-76861
https://bugzilla.redhat.com/show_bug.cgi?id=2162547
https://moodle.org/mod/forum/discuss.php?d=443273#p1782022
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-76861
https://bugzilla.redhat.com/show_bug.cgi?id=2162547
https://moodle.org/mod/forum/discuss.php?d=443273#p1782022

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