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Cookie not Marked as HttpOnly Identified on Target Web Application

Netsparker identified a cookie not marked as HTTPOnly.

HTTPOnly cookies cannot be read by client-side scripts, therefore marking a cookie as HTTPOnly can provide an additional layer of protection against cross-site scripting attacks.


During a cross-site scripting attack, an attacker might easily access cookies and hijack the victim's session.

Actions to Take

  1. See the remedy for solution.
  2. Consider marking all of the cookies used by the application as HTTPOnly. (After these changes javascript code will not be able to read cookies.)


Mark the cookie as HTTPOnly. This will be an extra layer of defense against XSS. However this is not a silver bullet and will not protect the system against cross-site scripting attacks. An attacker can use a tool such as XSS Tunnel to bypass HTTPOnly protection.

External References

Go back to the Complete list of Vulnerability Checks.