CVE-2021-40695Network attack vector

Authenticated quiz-grade disclosure via web service

Published Jan 21, 2022 · Updated Aug 4, 2024

Improper access control in Moodle LMS allows remote authenticated users to view unreleased quiz grades through a quiz web service. The quiz web-service path returns the student's computed grade without enforcing its configured release state; Moodle has not disclosed the affected function. Student-level access is required, and the reported consequence is limited to early disclosure of that student's quiz grade.

CVSS severity4.3
Medium
EPSS probability0.85%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Moodle LMS allows remote authenticated users to view unreleased quiz grades through a quiz web service. The quiz web-service path returns the student's computed grade without enforcing its configured release state; Moodle has not disclosed the affected function. Student-level access is required, and the reported consequence is limited to early disclosure of that student's quiz grade.

The record

CVE
CVE-2021-40695
Published
Jan 21, 2022
Updated
Aug 4, 2024
Vendor
Moodle
Product
Moodle LMS
Classifications
T1213
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 21, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.11 to 3.11.2, 3.10 to 3.10.6, 3.9 to 3.9.9 and earlier unsupported versions

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Moodle · Moodle LMSversion=3.11 to 3.11.2, 3.10 to 3.10.6, 3.9 to 3.9.9 and earlier unsupported versions

Published CVSS scores

4.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1213Data from Information Repositories

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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