[Full-disclosure] Kmail <= 1.9.1 (table/frameset) DOS

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SilentHack.co.uk Vulnerability Research
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Background:
Kmail is a HTML compatible email client that comes installed by
default with the KDE desktop. This DOS requires HTML parsing to be
enabled. This can be done in Kmail by going to Settings -> Configure
Kmail ->Security -> and tick Prefer HTML to Plain Text.

Description:
Kmail can be crashed due to incorrectly parsing certain HTML elements. In
this case the a combination of the <table> and <frameset> tags are
incorrectly parsed leading to a segmentation fault. A sample mail can be
found here http://silenthack.co.uk/nnp/exploits/kmail/tableCrash .

To reproduce the crash, copy the above mail into your local mail spool file
(e.g /var/mail/`whoami`) or send it to yourself (without the email headers
obviously). Double click the new mail and when it opens close it again. On
closing it the program should crash and give the following stack trace:

[KCrash handler]
#6 0xb790a334 in free () from /lib/tls/i686/cmov/libc.so.6
#7 0xb7aab8b1 in operator delete () from /usr/lib/libstdc++.so.6
#8 0xb7aab8fd in operator delete[] () from /usr/lib/libstdc++.so.6
#9 0xb6cd05d8 in non-virtual thunk to
DOM::HTMLObjectBaseElementImpl::~HTMLObjectBaseElementImpl() () from
/usr/lib/libkhtml.so.4
#10 0x084de030 in ?? ()
#11 0x084d03e8 in ?? ()
#12 0x00000001 in ?? ()
#13 0xb6e43aec in ?? () from /usr/lib/libkhtml.so.4
#14 0x084d03e8 in ?? ()
#15 0x00000000 in ?? ()

Version information:
Tested on KDE 3.5.2 and kmail 1.9.1.

Credits:
nnp

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http://silenthack.co.uk
http://smashthestack.org