Auth bypass in Moodle

CVE-2021-40693

An authentication bypass risk was identified in the external database authentication functionality, due to a type juggling vulnerability.

Vulnerability class: Broken Authentication

EPSS: 0.008 (53.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

Affected products

Moodle
N/a Moodle — versions 3.11 to 3.11.2, 3.10 to 3.10.6, 3.9 to 3.9.9 and earlier unsupported versions

Weakness classification (CWE)

CWE-287 — Improper Authentication

Public proof-of-concept exploits

jev770/badmoodle-scan

References

secalert@redhat.com (Third Party Advisory, x_refsource_MISC, Issue Tracking)

Frequently asked questions

What is CVE-2021-40693?: CVE-2021-40693 is a medium-severity vulnerability in Moodle, classified under Improper Authentication. CVSS score: 6.5/10. Published 2022-09-29.
How severe is CVE-2021-40693?: Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2021-40693 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.