Bug 2431706 (CVE-2021-47857)

Summary: CVE-2021-47857 moodle: Moodle: Arbitrary code execution via persistent cross-site scripting in calendar event subtitle
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Moodle. A remote attacker with privileges to create calendar events could exploit a persistent cross-site scripting (XSS) vulnerability in the calendar event subtitle field. By injecting malicious JavaScript into the subtitle track label of a crafted calendar event, the attacker could execute arbitrary code in the context of other users who view the event.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-01-21 18:04:08 UTC
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.