Google's Blogger.com classic HTTP response splitting vulnerability

[Meder Kydyraliev <meder () o0o nu>]

        Blogger.com classic HTTP response splitting vulnerability
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

0. Original Advisory
~~~~~~~~~~~~~~~~~~~
http://o0o.nu/~meder/o0o_Blogger_HTTP_response_splitting.txt


I. Background
~~~~~~~~~~~~~

Blogger.com is Google's blogging service.


II. Description
~~~~~~~~~~~~~~~

Blogger's personal page redirection mechanism contains a classic HTTP
response splitting vulnerability in the "Location" HTTP header. The
problem occurs due to use of unsanitized user-supplied data in the
"Location" HTTP header, which enables attacker to inject CRLF(%0d%0a)
characters thus splitting server's response taking full control over
the contents of second HTTP response. Exploitation of the vulnerability
can lead to cross-site scripting (XSS), cache poisioning and phishing
attacks.

The following URL was taking contents of query string and using it in
"Location" HTTP header without proper sanitation:

http://www.blogger.com/r?[URL here]


III. Vendor status 
~~~~~~~~~~~~~~~~~~

Vulnerability has been fixed on 13/01/2006


IV. Disclosure timeline
~~~~~~~~~~~~~~~~~~~~~~~

02/01/2006 - Issue discovered. Vendor notified.
02/01/2006 - Initial vendor response.
12/01/2006 - Vendor inquired on status.
13/01/2006 - Vendor response and confirmation that bug fixed.


V. References
~~~~~~~~~~~~~

1. http://www.packetstormsecurity.org/papers/general/whitepaper_httpresponse.pdf


-- 
http://o0o.nu/~meder
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