CVE-2021-37391Public exploitNetwork attack vector

Administrator session theft via unfiltered invitation content

Published Aug 10, 2021 · Updated Aug 4, 2024

Stored XSS in Chamilo LMS 1.11.14 allows remote authenticated users to steal cookies or run script in an administrator's browser. The sendInvitationToUser method passes attacker-controlled invitation content to MessageManager::send_message without stripping HTML tags. Exploitation requires a low-privileged account and an administrator to view the stored invitation; script execution is confined to the administrator's browser context.

CVSS severity5.4
Medium
EPSS probability2.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Chamilo LMS 1.11.14 allows remote authenticated users to steal cookies or run script in an administrator's browser. The sendInvitationToUser method passes attacker-controlled invitation content to MessageManager::send_message without stripping HTML tags. Exploitation requires a low-privileged account and an administrator to view the stored invitation; script execution is confined to the administrator's browser context.

The record

CVE
CVE-2021-37391
Published
Aug 10, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1539
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 10, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1539Steal Web Session Cookie

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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