A vulnerability and multiple security issues have been reported in DotNetNuke, which can be exploited by malicious users to compromise a vulnerable system and by malicious users and malicious people to bypass certain security restrictions.

1) An error when soft-deleting users can be exploited to undelete a user by re-registering with the same credentials.

2) An error in the application when validating user permissions in certain management functions can be exploited to gain access to certain admin functions.

3) An error in the application when verifying uploaded files can be exploited to execute certain arbitrary code.

Successful exploitation requires the permission to upload files.

4) An error when granting edit permissions for a page or a module can lead to the user being granted all permissions.

NOTE: A weakness in the login control, which could lead to disclosure of rejected credentials has also been reported.

Solution
Update to version 5.6.3.

Provided and/or discovered by
The vendor credits:
1) Robb Bryn
2, 3) Simon Meraner
4) Laurence Neville

Original Advisory
DotNetNuke:
http://www.dotnetnuke.com/News/Security-Policy/security-bulletin-no.52.aspx
http://www.dotnetnuke.com/News/Security-Policy/security-bulletin-no.53.aspx
http://www.dotnetnuke.com/News/Security-Policy/security-bulletin-no.54.aspx
http://www.dotnetnuke.com/News/Security-Policy/security-bulletin-no.55.aspx
http://www.dotnetnuke.com/News/Security-Policy/security-bulletin-no.56.aspx

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