CVE-2021-26746Public exploitNetwork attack vector

Reflected XSS via unvalidated agenda type parameter

Published Feb 19, 2021 · Updated Aug 3, 2024

Cross-site scripting in Chamilo LMS 1.11.14 allows remote attackers to execute script in a user's browser via a crafted agenda URL. The main/calendar/agenda_list.php handler accepted the type query parameter without restricting it to the four valid agenda categories, enabling attribute injection. Exploitation requires a user to load the crafted URL and trigger its injected event handler, exposing data and actions available to that browser session.

CVSS severity6.1
Medium
EPSS probability0.99%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Chamilo LMS 1.11.14 allows remote attackers to execute script in a user's browser via a crafted agenda URL. The main/calendar/agenda_list.php handler accepted the type query parameter without restricting it to the four valid agenda categories, enabling attribute injection. Exploitation requires a user to load the crafted URL and trigger its injected event handler, exposing data and actions available to that browser session.

The record

CVE
CVE-2021-26746
Published
Feb 19, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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 privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.1OSVCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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