CVE-2021-36401 json
Moodle vulnerable to Stored Cross-site Scripting
published 2023-03-06 3 y ago modified 2026-09-08 2 mo ago also BIT-moodle-2021-36401 , EUVD-2023-1009 , GHSA-g6h6-4fp6-w33w
- cvss
- 4.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 45%
- public exploits
- 0
- none known
Summary
In Moodle, ID numbers exported in HTML data formats required additional sanitizing to prevent a local stored XSS risk.
Patch / fix
- packagist moodle/moodle 3.9.8, 3.10.5, 3.11.1
- bitnami moodle 3.9.8, 3.10.5, 3.11.1
- moodle moodle 3.9.8, 3.10.5, 3.11.1
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 20 mo ago
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 4.8 | CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| GitHub | 3.1 | 4.8 | CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVD | 3.1 | 4.8 | CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| CNA | 3.1 | 4.8 | CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| OSV | 3.1 | 4.8 | CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| packagist | moodle/moodle | >=3.11.0-beta, <3.11.1 >=3.10.0-beta, <3.10.5 <3.9.8 |
3.11.1 3.10.5 3.9.8 |
| bitnami | moodle | <3.9.8 >=3.10.0, <3.10.5 >=3.11.0, <3.11.1 |
3.9.8 3.10.5 3.11.1 |
Affected products
- n/a Moodle
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
moodle.org
/mod/forum/discuss.php?d=424807
web, patch, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-36401
advisory, web
-
github.com
/moodle/moodle
package
Sources
- CVE List CVE-2021-36401
- GitHub Advisory GHSA-g6h6-4fp6-w33w
- NVD CVE-2021-36401
- OSV BIT-moodle-2021-36401
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.