CVE-2021-43560

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-11-22 · updated 2026-06-17
Weakness: CWE-863

Description

A flaw was found in Moodle in versions 3.11 to 3.11.3, 3.10 to 3.10.7, 3.9 to 3.9.10 and earlier unsupported versions. Insufficient capability checks made it possible to fetch other users' calendar action events.

Affected products

Fedoraproject Extra Packages For Enterprise Linux: 7.0
Fedoraproject Fedora: 35
Moodle: through 3.8.8; from 3.9.0 before 3.9.11; from 3.10.0 before 3.10.8; from 3.11.0 before 3.11.4 — fixed in 3.10.8, 3.11.4, 3.9.11

How to fix

Upgrade to a fixed version: Moodle 3.10.8, 3.11.4, 3.9.11. Check the vendor advisory for mitigations.

References

https://bugzilla.redhat.com/show_bug.cgi?id=2021519
https://moodle.org/mod/forum/discuss.php?d=429100
https://bugzilla.redhat.com/show_bug.cgi?id=2021519
https://moodle.org/mod/forum/discuss.php?d=429100

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