CVE-2021-47857

Moodle 3.10.3 contains a persistent cross-site scripting vulnerability in the calendar event subtitle field that allows attackers to inject malicious scripts. Attackers can craft a calendar event with malicious JavaScript in the subtitle track label to execute arbitrary code when users view the event.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://moodle.org/	Product
https://www.exploit-db.com/exploits/49714	Exploit Third Party Advisory VDB Entry
https://www.vulncheck.com/advisories/moodle-label-persistent-cross-site-scripting	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:moodle:moodle:3.10.3:*:*:*:*:*:*:*

History

17 Jun 2026, 04:18

Type	Values Removed	Values Added
Summary		(es) Moodle 3.10.3 contiene una vulnerabilidad de cross-site scripting persistente en el campo del subtítulo del evento del calendario que permite a los atacantes inyectar scripts maliciosos. Los atacantes pueden crear un evento de calendario con JavaScript malicioso en la etiqueta de la pista del subtítulo para ejecutar código arbitrario cuando los usuarios ven el evento.

05 Mar 2026, 19:45

Type	Values Removed	Values Added
First Time		Moodle moodle Moodle
CPE		cpe:2.3:a:moodle:moodle:3.10.3:::::::*
References	~~() https://moodle.org/ -~~	() https://moodle.org/ - Product
References	~~() https://www.exploit-db.com/exploits/49714 -~~	() https://www.exploit-db.com/exploits/49714 - Exploit, Third Party Advisory, VDB Entry
References	~~() https://www.vulncheck.com/advisories/moodle-label-persistent-cross-site-scripting -~~	() https://www.vulncheck.com/advisories/moodle-label-persistent-cross-site-scripting - Third Party Advisory

21 Jan 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-21 18:16

Updated : 2026-06-17 04:18

NVD link : CVE-2021-47857

Mitre link : CVE-2021-47857

CVE.ORG link : CVE-2021-47857

JSON object : View

Products Affected

moodle

moodle

CWE

CWE-79

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

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