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

CVE-2017-9387

Severity Medium
Score 5.4/10

Summary

An issue was discovered on Vera VeraEdge 1.7.19 and Veralite 1.7.481 devices. The device provides a shell script called relay.sh which is used for creating new SSH relays for the device so that the device connects to Vera servers. All the parameters passed in this specific script are logged to a log file called log.relay in the /tmp folder. The user can also read all the log files from the device using a script called log.sh. However, when the script loads the log files it displays them with content-type text/html and passes all the logs through the ansi2html binary which converts all the character text including HTML meta-characters correctly to be displayed in the browser. This allows an attacker to use the log files as a storing mechanism for the XSS payload and thus whenever a user navigates to that log.sh script, it enables the XSS payload and allows an attacker to execute his malicious payload on the user's browser.

  • LOW
  • NETWORK
  • LOW
  • CHANGED
  • REQUIRED
  • LOW
  • 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