UPDATE: We released Subtext 2.0 which also includes the fix for this vulnerability among many other bug fixes.

A Subtext user reported a security vulnerability due to a flaw in our integration with the FCKEditor control which allows someone to upload files into the images directory without being authenticated.

As far as we know, nobody has been seriously affected, but please update your installation as soon as possible. Our apologies for the inconvenience.

The fix should be relatively quick and painless to apply.

The Fix

If you’re running Subtext 1.9.* we have a fix available consisting of a single assembly, Subtext.Providers.BlogEntryEditor.FCKeditor.dll. After you download it (Subtext1.9.5-PATCH.zip 7.72KB) , unzip the assembly (I recommend backing up your old one just in case) and copy it into your bin directory.

Alternative Workaround

If you’re running a customized version and the above patch causes problems, you can workaround this issue by backing up and then temporarily removing the following directory in your installation.

Providers\BlogEntryEditor\FCKeditor\editor\filemanager

Notes

The Subtext team takes security very seriously and we regret that this flaw made it into our system. We appreciate that a user discretely brought it to our attention and worked quickly to create and test a patch. I went ahead and updated the release on SourceForge (if you’ve downloaded Subtext-1.9.5b then you’re safe) so that no new downloads are affected.

The code also has been fixed in Subversion in case you’re running a custom built version of Subtext.

I will follow up with a post later describing the issue in more detail and what we plan to do to mitigate such risks in the future. I’ll also write a post outlining general guidelines for reporting and handling security issues in an open source project based on guidance provided by the Karl Fogel book, Producing Open Source Software.

Again, I am sorry for any troubles and inconvenience this may have caused. If you know any Subtext users, please let them know. I’ll be updating the website momentarily.

Download

Again, here is the patch location.