CVE-2021-20282Network attack vector

Account activation via bypassed email verification secret

Published Mar 15, 2021 · Updated Aug 3, 2024

Incorrect authorization in affected Moodle LMS releases allows remote attackers to confirm a new account without its email secret. The account-confirmation handler accepts a crafted request without establishing possession of the secret embedded in the verification link. Sites must allow email-based account creation, and successful exploitation activates an attacker-created account.

CVSS severity5.3
Medium
EPSS probability1.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in affected Moodle LMS releases allows remote attackers to confirm a new account without its email secret. The account-confirmation handler accepts a crafted request without establishing possession of the secret embedded in the verification link. Sites must allow email-based account creation, and successful exploitation activates an attacker-created account.

The record

CVE
CVE-2021-20282
Published
Mar 15, 2021
Updated
Aug 3, 2024
Vendor
Moodle
Product
Moodle LMS
Classifications
CWE-863, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 15, 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=Fixed in 3.10.2, 3.9.5, 3.8.8, 3.5.17

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Moodle · Moodle LMSversion=Fixed in 3.10.2, 3.9.5, 3.8.8, 3.5.17

Published CVSS scores

5.3GitLab Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
T1190Exploit Public-Facing Application

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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