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

Published · last modified .

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.

EPSS exploit prediction

EPSS: 0.008 (56.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-40693: held from 0.008 to 0.008.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

  • Moodle
  • 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)

Public proof-of-concept exploits

References

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.