TYPO3 Core

You can still disable the install tool globally by inserting a die() to typo3/install/index.php or just removing the folder typo3/install/.

According to the scenario you described:
If there is an extension or any other insecure part of a website which allows to write new files and fill them with code, it probably would also be possible to write PHP code to that file. Thus, the install tool isn't required any more to cause damage to a site. This could be done directly by calling this newly created file via browser (e.g. typo3conf/malware.php).

IMO the website admin has to take care which (insecure) extensions are installed and to upgrade the server environment (apache, libs, whatever) to the latest secure releases. Just my two cents, what do others think?

Of course you can still disable the install tool (the comment in line 49 says exactly that :) ), but i think many users just use the defaults and don't change the typo3_src files, not to mention securing their installs according to the "TYPO3 Security Cookbook".

Personally, I appreciate the new approach, since you don't need to enable all likeinstall tools for every site using the source at once! One the other side the new way is more insecure than the old way in allowing more possible attacks.

I don't get your point about this. Do you suggest to remove the functionality, or would you like to keep it?

Obviously the feature is just as secure as the installation itself is. If you are paranoid, edit typo3/install/index.php like you had to do before. It's just the default setting that has changed.

Resolved, no change required:

- No further feedback for a long time
- Install tool can easily be disabled in typo3/install/index.php in line 50 by making the if statement evaluate to true.
- An attacker who gains access to the system through core / extensions probably doesn't need to access the install tool to evolve further malicious actions.