CVE-2021-36396
Moodle vulnerable to Server-Side Request Forgery
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
- Record
CVE-2021-36396- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
CVE List
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
- Record
CVE-2021-36396- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
EUVDEUVD-2023-0870
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
- Record
EUVD-2023-0870- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-4rmj-w58m-fvch
Moodle vulnerable to Server-Side Request Forgery
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
- Record
GHSA-4rmj-w58m-fvch- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
OSV
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
- Record
CVE-2021-36396- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVGHSA-4rmj-w58m-fvch
Moodle vulnerable to Server-Side Request Forgery
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
- Record
GHSA-4rmj-w58m-fvch- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-36396
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
- Record
UBUNTU-CVE-2021-36396- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVBIT-moodle-2021-36396 No score
In Moodle, insufficient redirect handling made it possible to blindly bypass cURL blocked hosts/allowed ports restrictions, resulting in a blind SSRF risk.
- Record
BIT-moodle-2021-36396- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
moodle/moodlePackagist |
3.11.0-beta up to 3.11.1 | 3.11.1 |
moodle/moodlePackagist |
3.10.0-beta up to 3.10.5 | 3.10.5 |
moodle/moodlePackagist |
before 3.9.8 | 3.9.8 |
moodleBitnami |
before 3.9.8, 3.10.0 up to 3.10.5, 3.11.0 up to 3.11.1 | 3.9.83.10.53.11.1 |
moodle/moodlePackagist |
3.11.0-beta up to 3.11.1, plus listed versions v3.11.0v3.11.0-betav3.11.0-rc1v3.11.0-rc2 |
3.11.1 |
moodle/moodlePackagist |
3.10.0-beta up to 3.10.5, plus listed versions v3.10.0v3.10.0-betav3.10.0-rc1v3.10.0-rc2v3.10.1v3.10.2v3.10.3v3.10.4 |
3.10.5 |
moodle/moodlePackagist |
before 3.9.8, plus listed versions v2.3.10v2.3.11v2.3.4v2.3.5v2.3.6 Show 45 moreShow lessv2.3.7v2.3.8v2.3.9v2.4.0v2.4.0-rc1v2.4.1v2.4.10v2.4.11v2.4.2v2.4.3v2.4.4v2.4.5v2.4.6v2.4.7v2.4.8v2.4.9v2.5.0v2.5.0-betav2.5.0-rc1v2.5.1v2.5.2v2.5.3v2.5.4v2.5.5v2.5.6v2.5.7v2.5.8v2.5.9v2.6.0v2.6.0-betav2.6.0-rc1v2.6.1v2.6.10v2.6.11v2.6.2v2.6.3v2.6.4v2.6.5v2.6.6v2.6.7v2.6.8v2.6.9v2.7.0v2.7.0-betav2.7.0-rc1 |
3.9.8 |
moodleUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 2.7.9+dfsg-12.7.10+dfsg-12.7.11+dfsg-12.7.11+dfsg-22.7.12+dfsg-13.0.3+dfsg-0ubuntu13.0.3+dfsg-0ubuntu1+esm1 |
None known |
moodleUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 3.0.3+dfsg-0ubuntu13.0.3+dfsg-0ubuntu1+esm1 |
None known |
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | T0X1Cx/CVE-2021-36396-Moodle-Time-Based-SQLi-Exploit | 2023-11-04 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-36396 is a high vulnerability (CVSS 7.5) in Moodle, published March 6, 2023. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 1.43%, the 73rd percentile. Fixed in moodle/moodle 3.11.1.
References
Left out here: 205 versions. The JSON record has them.