7.5

CVE-2021-36396: moodle Server-Side Request Forgery (SSRF)

CVSS: 7.5v3.1HighModified
AliasesUBUNTU-CVE-2021-36396
Published 06-03-2023Last modified 05-03-2025
Open JSON

Vulnerability summary

CVE-2021-36396 is a high (CVSS 7.5) Server-Side Request Forgery (SSRF) vulnerability in moodle. EPSS estimates a 1.43% chance of exploitation in the next 30 days, higher than 72.7% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
1.43%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 06-03-2023
    PublishedVulnerability first disclosed.
  2. 05-03-2025
    Last modifiedVulnerability information updated.

Description

In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

1.43%

Chance of exploitation in the next 30 days

Percentile

73%

Versus all other CVEs

30-day change

0.00 pp

From 1.43% on 21-09-2026

21-09-202621-10-2026
EPSS score
1.43%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected 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

References

3 links