1. OVERVIEW

SilverStripe 2.4.7 and lower versions are vulnerable to Open URL Redirection.


2. BACKGROUND

SilverStripe CMS is easy for both developers and content authors to
work with. The SilverStripe Framework keeps the code tucked away
neatly so that it can be accessed easily by programmers but does not
get in the way of content authors.


3. VULNERABILITY DESCRIPTION

SilverStripe CMS contains a flaw that allows a remote cross site
redirection attack. This flaw exists because the application does not
validate the "BackURL" parameter upon submission to the
"/index.php/Security/login" script. This could allow a user to create
a specially crafted URL, that if clicked, would redirect a victim from
the intended legitimate web site to an arbitrary web site of the
attacker's choosing.


4. VERSIONS AFFECTED

Tested on 2.4.7


5. PROOF-OF-CONCEPT/EXPLOIT

http://localhost/index.php/Security/login?BackURL=//yehg.net


6. SOLUTION

Upgrade to the latest 3.x version.


7. VENDOR

SilverStripe Development Team
http://www.silverstripe.org/


8. CREDIT

This vulnerability was discovered by Aung Khant, http://yehg.net, YGN
Ethical Hacker Group, Myanmar.


9. DISCLOSURE TIME-LINE

2012-02-06: notified vendor
2012-10-15: vulnerability disclosed


10. REFERENCES

Original Advisory URL:
http://yehg.net/lab/pr0js/advisories/%5BSilverStripe_2.4.7%5D_url_redirection

#yehg [2012-10-15]

---------------------------------
Best regards,
YGN Ethical Hacker Group
Yangon, Myanmar
http://yehg.net
Our Lab | http://yehg.net/lab
Our Directory | http://yehg.net/hwd