Avant Browser - Same of Origin Policy Bypass

Avant Browser - Same of Origin Policy Bypass - browser:home

Details

Vendor Site: Avant browser (www.avantbrowser.com)
Date: December, 5 2012 – CVE (TBA)

Affected Software: Avant Browser Ultimate 2012 Build 28 and potentially previous versions
Status: Unpatched
Researcher: Roberto Suggi Liverani - @malerisch
PDF version: Avant_multiple_vulnerabilities_advisory.pdf

Same of Origin Policy Bypass

A malicious user can execute arbitrary JavaScript/HTML code on the privileged browser:home page from an untrusted web page on Internet (http:// zone). This is possible by creating an iframe element pointing to the browser:home page and then invoking privileged commands using a window object reference to the iframe element, as shown in the example below:

<iframe name="test2" src="browser:home"></iframe>

<script>window['test2'].navigator.AFRunCommand(id_of_privileged_command, vstr)</script>

This code allows interaction from an untrusted zone (http://) to a trusted and privileged zone: browser:home.

Exploitation

This vulnerability can be exploited in several ways. As the injection point is in the browser: privileged browser zone, it is possible to bypass Same Origin Policy (SOP) protections, and also access Avant Browser native JavaScript privileged functions which can be invoked using the window.navigator object (e.g. window.navigator.*). Such Avant Browser object interfaces can be used to read browser history, bookmarks, or modify Avant Browser configuration. Below, an example of code which allows to read the browser's history is provided.

Exploit - Stealing browser's history

<iframe name="test2" src="browser:home"></iframe>
<script> var vstr = {value: ""}; window['test2'].navigator.AFRunCommand(60003, vstr) alert(vstr.value);
//send vstr.value via an img src to another domain </script>

BeEF module

A BeEF module has been developed which steals history of the Avant browser. The BeEF module can be found below:

https://github.com/malerisch/beef/tree/avant_browser/modules/exploits/avant_steal_history

Video

Avant Browser - BeEF - History Stealing exploit video

Timeline

07/03/2012 - Posted 10 posts to a forum to get a security contact
14/03/2012 - Reception of report confirmed but no further reply
14/03/2012 - Chased them, no reply
03-05/2012 - 2 new releases following the report, one bug silently fixed
12/05/2012 - HITB2012AMS - bug disclosed during presentation
14/11/2012 - HackPra - bug and exploit module presented

Solution

Do not use Avant browser.

TrendMicro ScanMail for Microsoft Exchange (SMEX) predictable session token - CVE-2015-3326

It's time for another advisory ( CVE-2015-3326 ), a simple one, for a vulnerability which can be found quickly and trivially. For those of you who just want to give a glance at the post, I suggest to directly watch the picture which says it all! The following vulnerability was discovered on TrendMicro SMEX (ScanMail for Microsoft Exchange) 10 SP2 but it affects other versions as well. While surfing the SMEX web administrative interface using a web proxy, I have noticed something in the HTTP request - the session token itself and its format, a number. After observing a significant number of logins, the session token was always represented with an number composed of minimum 4 digits and maximum 5 digits, as shown in the screen shot below: Although the observed session tokens were never generated sequentially, the lack of a cryptographically strong PRNG for the session identifier, allows a malicious user to trivially guess the token. This attack can be easily automated.

Alcatel Lucent Omnivista or: How I learned GIOP and gained Unauthenticated Remote Code Execution (CVE-2016-9796)

It is time for another advisory or better a blog post about Alcatel Lucent Omnivista and its vulnerabilities. Omnivista is a central management network tool and it is typically used in medium/large organisation with a complex VoIP/SIP infrastructure. Interestingly enough, this software belongs to the niche of "undownloadable" software and it requires a license to work as well. My "luck" came during an engagement where it was already installed and this post documents one of the many 0days discovered during such audit. The reasons why I wanted to dedicate a single blog post on this vulnerability are several. First, remote code execution (RCE) is always a sweet bug to show. Second, I strongly believe that documenting vulnerabilities in applications using old protocols and standards, respectively GIOP and CORBA, can be beneficial for the infosec community, since no many examples of vulnerabilities in such applications are available or published on the Interne

Microsoft .NET MVC ReDoS (Denial of Service) Vulnerability - CVE-2015-2526 (MS15-101)

Microsoft released a security bulletin ( MS15-101 ) describing a .NET MVC Denial of Service vulnerability ( CVE-2015-2526 ) that I reported back in April. This blog post analyses the vulnerability in details, starting from the theory and then providing a PoC exploit against a MVC web application developed with Visual Studio 2013. For those of you who want to see the bug, you can directly skip to the last part of this post or watch the video directly... ;-) A bit of theory The .NET framework (4.5 tested version) uses backtracking regular expression matcher when performing a match against an expression. Backtracking is based on the NFA (non-deterministic finite automata) algorithm engine which is designed to validate all input states. By providing an “evil” regex expression – an expression for which the engine can be forced to calculate an exponential number of states - it is possible to force the engine to calculate an exponential number of states, leading to a condition defined su

malerisch.net

Search This Blog