CVE-2023-5543: Moodle: duplicating a bigbluebutton activity assigns the same meeting id

Severity: low (CVSS 3.3 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: 2023-11-09 · updated 2026-06-17
Weakness: CWE-284

Description

When duplicating a BigBlueButton activity, the original meeting ID was also duplicated instead of using a new ID for the new activity. This could provide unintended access to the original meeting.

Affected products

Fedoraproject Extra Packages For Enterprise Linux: 7.0
Fedoraproject Fedora: 38
Moodle: from 4.0.0 before 4.0.11; from 4.1.0 before 4.1.6; from 4.2.0 before 4.2.3 — fixed in 4.0.11, 4.1.6, 4.2.3

How to fix

Upgrade to a fixed version: Moodle 4.0.11, 4.1.6, 4.2.3. Check the vendor advisory for mitigations.

References

http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-77795
https://bugzilla.redhat.com/show_bug.cgi?id=2243442
https://moodle.org/mod/forum/discuss.php?d=451584
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-77795
https://bugzilla.redhat.com/show_bug.cgi?id=2243442
https://moodle.org/mod/forum/discuss.php?d=451584

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