Secunia

Some vulnerabilities and a weakness have been reported in DotNetNuke, which can be exploited by malicious people to disclose certain information, cause a DoS (Denial of Service), manipulate certain data, and bypass certain security restrictions.

1) The problem is that it is possible to trigger the install / upgrade process, which can be exploited to cause a DoS by sending a large number of specially crafted requests or to re-execute the database scripts, resulting in data being overwritten or corrupted.

2) Errors in the logic for the UrlControl and the FileSystem API can be exploited to upload certain safe files (e.g. txt, jpg, or gif files) to restricted folders.

NOTE: "Safe" file extensions are defined in "Host Settings".

3) A weakness can be exploited to disclose the DotNetNuke version number.

The vulnerabilities and weakness are reported in versions 3.0 through 4.8.2.

Solution
Update to version 4.8.3.

Provided and/or discovered by
The vendor credits:
1) Tony Valenti and Joseph Ravioli
2) Tomotoshi Sugishita and Mitchell Sellers

Original Advisory
http://www.dotnetnuke.com/News/SecurityPolicy/SecurityBulletinno14/tabid/1159/Default.aspx
http://www.dotnetnuke.com/News/SecurityPolicy/SecurityBulletinno15/tabid/1160/Default.aspx
http://www.dotnetnuke.com/News/SecurityPolicy/SecurityBulletinno16/tabid/1161/Default.aspx
http://www.dotnetnuke.com/News/SecurityPolicy/SecurityBulletinno17/tabid/1162/Default.aspx

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