CVE-2021-36402: moodle Improper Input Validation
CVSS: 5.3v3.1MediumModified
AliasesUBUNTU-CVE-2021-36402
Published 06-03-2023Last modified 07-03-2025
Vulnerability summary
CVE-2021-36402 is a medium (CVSS 5.3) Improper Input Validation vulnerability in moodle. EPSS estimates a 0.53% chance of exploitation in the next 30 days, higher than 43.6% of scored vulnerabilities.
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)EPSS score
0.53%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 06-03-2023PublishedVulnerability first disclosed.
- 07-03-2025Last modifiedVulnerability information updated.
Description
In Moodle, Users' names required additional sanitizing in the account confirmation email, to prevent a self-registration phishing risk.
CVSS metrics
3 scores · 3 sources · 1 versionMedium 5.3Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS trend
Probability
0.53%
Chance of exploitation in the next 30 days
Percentile
44%
Versus all other CVEs
30-day change
0.00 pp
From 0.53% on 21-09-2026
21-09-202621-10-2026
EPSS score0.53%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Moodle1 product
- moodle< 3.9.8 | ≥ 3.10.0, < 3.10.5 | ≥ 3.11.0, < 3.11.1
Ubuntu1 product
- moodleAll versions (No fix recorded)
2 vendors · 2 products