Title:Buffer overflow in VinaGame Zing Chat
Reporter:Blue Moon Consulting
Products:VinaGame Zing Chat 1.1.3
Fixed in:--


VinaGame Zing Chat contains a buffer overflow error in its PPFTCtrl module that possibly allows an attacker to run arbitrary code. At the very least, the attacker is able to crash Zing Chat.

In parsing zing://RegisterPPDownLoadFileFunc protocol, input values are not length-checked. These values are later wcscpy and wcscat to local buffers resulting in buffer overflows.

The overflow would overwrite saved return address and give an attacker control over execution flow if not for the stack smashing protection built into the compiler. However, there is a slim chance that the attacker is able to predict the canary value and hence bypass this protection.


Do not click on any link that starts with zing://.


There is no fix at the moment. Customers are advised to contact the vendor directly for a proper fix.


Blue Moon Consulting adapts RFPolicy v2.0 in notifying vendors.

Initial vendor contact:
 May 08, 2008: alert sent via web form, auto-reply received from
Vendor response:
Public disclosure:
 May 15, 2008
Exploit code:The following Python snippet generates an overly long URL:
a = '<fdctt ver="1" jobid="C55F718A-3206-4A98-AA42-15B36054F010" tribeid="21569327264368" tribename="Th\xe1\xba\xbf Gi\xe\xbb\x9bi Phim" toolid="{4588C3CB-972A-43d5-A78E-E1BEE00E9E3E}" fileid="{268DCE6E-8406-65D6-F22B-15A876123862}" filename="barnyard.avi" tracker="" comid="1"/>'

b = a.replace("barnyard.avi", 'a' * 4000).encode("base64").replace("\n", "")

print "zing://RegisterPPDownLoadFileFunc/?content=%s" % b


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