FKIE_CVE-2021-47857

Vulnerability from fkie_nvd - Published: 2026-01-21 18:16 - Updated: 2026-03-05 19:45
Severity ?
7.2 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
6.1 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Summary
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.
References
disclosure@vulncheck.comhttps://moodle.org/Product
disclosure@vulncheck.comhttps://www.exploit-db.com/exploits/49714Exploit, Third Party Advisory, VDB Entry
disclosure@vulncheck.comhttps://www.vulncheck.com/advisories/moodle-label-persistent-cross-site-scriptingThird Party Advisory
Impacted products
Vendor Product Version
moodle moodle 3.10.3
To clipboard 

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  "id": "CVE-2021-47857",
  "lastModified": "2026-03-05T19:45:36.053",
  "metrics": {
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          "modifiedAttackVector": "NOT_DEFINED",
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          "valueDensity": "NOT_DEFINED",
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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.