CVE-2026-30884 Details
Description
mdjnelson/moodle-mod_customcert is a Moodle plugin for creating dynamically generated certificates with complete customization via the web browser. Prior to versions 4.4.9 and 5.0.3, a teacher who holds `mod/customcert:manage` in any single course can read and silently overwrite certificate elements belonging to any other course in the Moodle installation. The `core_get_fragment` callback `editelement` and the `mod_customcert_save_element` web service both fail to verify that the supplied `elementid` belongs to the authorized context, enabling cross-course information disclosure and data tampering. Versions 4.4.9 and 5.0.3 fix the issue.
A critical authorization bypass vulnerability has been identified in the Moodle Custom Certificate plugin, specifically in versions prior to 4.4.9 and 5.0.3. The vulnerability allows teachers with the 'mod/customcert:manage' capability in one course to read and silently overwrite certificate elements in other courses. This issue arises because the 'elementid' parameter, which is user-controlled, is not properly validated against the authorized context before being processed. As a result, attackers can exploit this flaw to access and modify certificate data across different courses within the same Moodle installation.
Users can update to Moodle Custom Certificate plugin versions 4.4.9 or 5.0.3 to address this vulnerability.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Mar 18, 2026CISA-ADP
Assessed Mar 18, 2026References to Advisories, Solutions, and Tools
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Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-639 | Authorization Bypass Through User-Controlled Key | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| mdjnelson/moodle-mod_customcert | All versions |
CPE
Remediation
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Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Mar 18, 2026 | New CVE Received | [email protected] |