CVE-2021-47857

Moodle 3.10.3 - 'label' Persistent Cross Site Scripting

Published: Jan 21, 2026Updated: Mar 5, 2026 Sources: CVE List NVD BDUCWE-79

7.2HIGH

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:CScope

Changed

Impact

C:LConfidentiality

Low

I:LIntegrity

Low

A:NAvailability

None

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Weaknesses

CWE-79

Affected Products

Moodle

oss-project·AUaka lms, jmol plugin

MoodleOn-premWeb App

Web & CMS Plugins / cms-core

Мартин Догиамас

individual-dev·AUaka martin dogiamas

MoodleOn-premWeb App

Web & CMS Plugins

and 1 more affected products View all →

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Execution

Initial Access

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References

https://www.exploit-db.com/exploits/49714

exploit-db.com

https://moodle.org/

moodle.org

https://www.vulncheck.com/advisories/moodle-label-persistent-cross-site-scripting

vulncheck.com

and 1 more references View all →

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Exploit details & PoC links

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