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Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVE-2021-21312

Medium
4.8/10

Summary

GLPI is open source software which stands for Gestionnaire Libre de Parc Informatique and it is a Free Asset and IT Management Software package. In GLPI before verison 9.5.4, there is a vulnerability within the document upload function (Home > Management > Documents > Add, or /front/document.form.php endpoint), indeed one of the form field: "Web Link" is not properly sanitized and a malicious user (who has document upload rights) can use it to deliver JavaScript payload. For example if you use the following payload: " accesskey="x" onclick="alert(1)" x=", the content will be saved within the database without any control. And then once you return to the summary documents page, by clicking on the "Web Link" of the newly created file it will create a new empty tab, but on the initial tab the pop-up "1" will appear.

  • LOW
  • NETWORK
  • LOW
  • CHANGED
  • REQUIRED
  • HIGH
  • LOW
  • NONE

CWE-79 - Cross Site Scripting

Cross-Site Scripting, commonly referred to as XSS, is the most dominant class of vulnerabilities. It allows an attacker to inject malicious code into a pregnable web application and victimize its users. The exploitation of such a weakness can cause severe issues such as account takeover, and sensitive data exfiltration. Because of the prevalence of XSS vulnerabilities and their high rate of exploitation, it has remained in the OWASP top 10 vulnerabilities for years.

References

Advisory Timeline

  • Published