CVE-2021-20280

Moodle Cross Site Scripting / Server-Side Request Forgery

Severity Score

5.4

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

Text-based feedback answers required additional sanitizing to prevent stored XSS and blind SSRF risks in moodle before 3.10.2, 3.9.5, 3.8.8, 3.5.17.

Las respuestas de retroalimentación basadas en texto requirieron saneamiento adicional para prevenir un ataque de tipo XSS almacenado y riesgos SSRF ciegos en moodle versiones anteriores a 3.10.2, 3.9.5, 3.8.8, 3.5.17

Moodle versions 3.10 to 3.10.1, 3.9 to 3.9.4, 3.8 to 3.8.7, and 3.5 to 3.5.16 suffer from cross site scripting and server-side request forgery vulnerabilities.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Medium

Authentication

Single

Confidentiality

None

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-12-17 CVE Reserved
2021-03-15 CVE Published
2024-08-03 CVE Updated
2024-08-03 First Exploit
2025-03-30 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CAPEC

References (6)

URL	Tag	Source
https://bugzilla.redhat.com/show_bug.cgi?id=1939037	Issue Tracking

URL	Date	SRC
http://packetstormsecurity.com/files/164817/Moodle-Cross-Site-Scripting-Server-Side-Request-Forgery.html	2024-08-03

URL	Date	SRC
https://moodle.org/mod/forum/discuss.php?d=419651	2023-11-07

URL	Date	SRC
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AFSNJ7XHVTC52RSRX2GBQFF3VEEAY2MS	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FGOMHMYM3WICJ6D6U22Z6LPJGT5A6MZM	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UFH5DDMU5TZ3JT4Q52WMRAHACA5MHIMT	2023-11-07

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Moodle Search vendor "Moodle"		Moodle Search vendor "Moodle" for product "Moodle"				>= 3.5.0 < 3.5.17 Search vendor "Moodle" for product "Moodle" and version " >= 3.5.0 < 3.5.17"		-		Affected
Moodle Search vendor "Moodle"		Moodle Search vendor "Moodle" for product "Moodle"				>= 3.8.0 < 3.8.8 Search vendor "Moodle" for product "Moodle" and version " >= 3.8.0 < 3.8.8"		-		Affected
Moodle Search vendor "Moodle"		Moodle Search vendor "Moodle" for product "Moodle"				>= 3.9.0 < 3.9.5 Search vendor "Moodle" for product "Moodle" and version " >= 3.9.0 < 3.9.5"		-		Affected
Moodle Search vendor "Moodle"		Moodle Search vendor "Moodle" for product "Moodle"				>= 3.10.0 < 3.10.2 Search vendor "Moodle" for product "Moodle" and version " >= 3.10.0 < 3.10.2"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				32 Search vendor "Fedoraproject" for product "Fedora" and version "32"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				33 Search vendor "Fedoraproject" for product "Fedora" and version "33"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				34 Search vendor "Fedoraproject" for product "Fedora" and version "34"		-		Affected