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openSIS <= 7.4 Incorrect Access Control Vulnerabilities
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[-] Software Link:

https://opensis.com/


[-] Affected Versions:

Version 7.4 and prior versions.


[-] Vulnerabilities Description:

The application prevents unauthenticated access to its functionalities 
by including
the 'RedirectIncludes.php', 'RedirectModules.php', and 
'RedirectRootInc.php' scripts,
which implement the access control logic by using the following code:

if(!$_SESSION['STAFF_ID'] && !$_SESSION['STUDENT_ID'] && 
strpos($_SERVER['PHP_SELF'],'index.php')===false)
{
     header('Location: ../../../index.php');
     exit;
}

This can be easily bypassed by appending /index.php at the end of the 
URL, and can
be exploited by unauthenticated attackers to potentially access any 
application
functionality which should require the user to be authenticated.


[-] Solution:

No official solution is currently available.


[-] Disclosure Timeline:

[04/11/2019] - Vendor notified
[04/11/2019] - Vendor acknowledgement
[10/01/2020] - Vendor contacted again asking for updates
[15/01/2020] - Vendor replied they would need a few examples
[20/01/2020] - Told the vendor they could use the PoC I sent them in 
November
[05/02/2020] - Vendor asked for a video recording to demonstrate the 
vulnerabilities
[06/02/2020] - Proof of Concept video sent to the vendor
[03/03/2020] - Vendor contacted again asking for updates
[04/03/2020] - Vendor replied "we just have to wait a little longer"
[25/04/2020] - Version 7.4 released, vulnerabilities still not fixed
[22/05/2020] - CVE number assigned
[30/06/2020] - Public disclosure


[-] CVE Reference:

The Common Vulnerabilities and Exposures project (cve.mitre.org)
has assigned the name CVE-2020-13382 to these vulnerabilities.


[-] Credits:

Vulnerabilities discovered by Egidio Romano.


[-] Original Advisory:

http://karmainsecurity.com/KIS-2020-06