CVE-2021-20187Network attack vector

Administrator PHP execution via Shibboleth data include

Published Jan 28, 2021 · Updated Aug 3, 2024

Code injection in Moodle LMS before 3.10.1, 3.9.4, 3.8.7, and 3.5.16 allows remote authenticated users to execute PHP scripts. The Shibboleth plugin passes its administrator-controlled convert_data path directly to include(), and affected releases permit that path to reference Moodle's writable data directory. Site-administrator access and enabled Shibboleth authentication are required; included code runs in the web-server process and can compromise the application and its data.

CVSS severity7.2
High
EPSS probability1.57%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code injection in Moodle LMS before 3.10.1, 3.9.4, 3.8.7, and 3.5.16 allows remote authenticated users to execute PHP scripts. The Shibboleth plugin passes its administrator-controlled convert_data path directly to include(), and affected releases permit that path to reference Moodle's writable data directory. Site-administrator access and enabled Shibboleth authentication are required; included code runs in the web-server process and can compromise the application and its data.

The record

CVE
CVE-2021-20187
Published
Jan 28, 2021
Updated
Aug 3, 2024
Vendor
Moodle
Product
Moodle LMS
Classifications
CWE-829, CWE-94, T1059
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jan 28, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=moodle 3.10.1, moodle 3.9.4, moodle 3.8.7, moodle 3.5.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Moodle · Moodle LMSversion=moodle 3.10.1, moodle 3.9.4, moodle 3.8.7, moodle 3.5.16

Published CVSS scores

7.2GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-829Inclusion of Functionality from Untrusted Control Sphere
CWE-94Improper Control of Generation of Code ('Code Injection')
T1059Command and Scripting Interpreter

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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