Description
Moodle 4.2.0 through 4.5.15, 5.0.0 through 5.0.11, 5.1.0 through 5.1.8, 5.2.0 through 5.2.4, and 5.3.0 contain an information disclosure vulnerability in the core_grades_get_feedback web service. The service lacks group-membership and enrolment checks, so non-editing teachers can iterate userid values to read other groups' grade feedback and users' names and identity fields such as email.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Moodle Project | moodle | 5.3.0, 5.2.0 – ≤ 5.2.4, 5.1.0 – ≤ 5.1.8, 5.0.0 – ≤ 5.0.11, 4.2.0 – ≤ 4.5.15 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | moodle | No fix yet | — |
| Ubuntu Pro 16.04 LTS | moodle | No fix yet | — |
Advisories 1
- WID-SEC-2026-4274 Moodle: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 1, 2026
References
- https://github.com/moodle/moodle/blob/v5.3.0/public/grade/classes/external/get_feedback.php#L77-L96 technical-description
- https://abraxaslabs.tech/research/moodle-grades-feedback-idor third-party-advisory
- https://github.com/moodle/moodle product
- VulnCheck Advisory: Moodle through 5.3.0, 5.2.4, 5.1.8, 5.0.11 and 4.5.15 Information Disclosure via core_grades_get_feedback third-party-advisory