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

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 : 2026-03-05 19:45

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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