Gadu-Gadu Remote DoS (all versions)

Product: Tlen.pl (<= 5.23.4.1)
Vendor: o2.pl Sp. z o.o. (http://www.tlen.pl/&#41;
Impact: Remote script execution
Severity: High
Authors: Blazej Miga <[email protected]>,
Jaroslaw Sajko <[email protected]>
Date: 20/12/04

[ISSUE]

Tlen.pl is the instant messenger application used by more than 700 000
users.
There is a vulnerability in message parsing which allows remote execution
of arbitrary script.

[DETAILS]

There is a parsing error. We can send a malicious string which has an url
inside. This url can be a javascript code for example. Code will execute
when the window with the message pops up.

[POF]

Send such a string to any receipent:
www.tlen.pl"style=background-image:url(javascript:alert(%22You%20are%20owned!%22));.pl

[SOLUTION]

Please upgrade to the newest version (5.23.4.2)

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