CVE-2021-47857

7.2 HIGH
Published: January 21, 2026 Modified: March 05, 2026
View on NVD

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://moodle.org/
Source: disclosure@vulncheck.com
Product
https://www.exploit-db.com/exploits/49714
Source: disclosure@vulncheck.com
Exploit Third Party Advisory VDB Entry
https://www.vulncheck.com/advisories/moodle-label-persistent-cross-site-scripting
Source: disclosure@vulncheck.com
Third Party Advisory

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.2 / 10.0
EPSS (Exploit Probability)
0.0%
9th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

CWE-79

Affected Vendors

moodle

Related CVEs

CVE-2026-4572 6.3
CVE-2026-4571 6.3
CVE-2026-4570 6.3
CVE-2025-10736 6.5
CVE-2026-4569 6.3