CVE-2023-35131: Moodle: xss risk on groups page

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-06-22 · updated 2026-06-17
Weakness: CWE-79

Description

Content on the groups page required additional sanitizing to prevent an XSS risk. This flaw affects Moodle versions 4.2, 4.1 to 4.1.3, 4.0 to 4.0.8 and 3.11 to 3.11.14.

Affected products

Moodle: from 3.11.0 before 3.11.15; from 4.0.0 before 4.0.9; from 4.1.0 before 4.1.4; 4.2.0 — fixed in 3.11.15, 4.0.9, 4.1.4

How to fix

Upgrade to a fixed version: Moodle 3.11.15, 4.0.9, 4.1.4. Check the vendor advisory for mitigations.

References

https://bugzilla.redhat.com/show_bug.cgi?id=2214369
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7A72KX4WU6GK2CX4TKYFGFASPKOEOJFC/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I5QAEAGJ44NVXLAJFJXKARKC45OGEDXT/
https://moodle.org/mod/forum/discuss.php?d=447829
https://bugzilla.redhat.com/show_bug.cgi?id=2214369
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7A72KX4WU6GK2CX4TKYFGFASPKOEOJFC/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I5QAEAGJ44NVXLAJFJXKARKC45OGEDXT/
https://moodle.org/mod/forum/discuss.php?d=447829

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