Exploiting Wildcards On Linux/Unix

An anonymous reader writes: DefenseCode researcher Leon Juranic found security issues related to using wildcards in Unix commands. The topic has been talked about in the past on the Full Disclosure mailing list, where some people saw this more as a feature than as a bug. There are clearly a number of potential security issues surrounding this, so Mr. Juranic provided five actual exploitation examples that stress the risks accompanying the practice of using the * wildcard with Linux/Unix commands. The issue can be manifested by using specific options in chown, tar, rsync etc. By using specially crafted filenames, an attacker can inject arbitrary arguments to shell commands run by other users — root as well.

Comments

User data to control commands

[jones_supa]

Systems where user data can accidentally get mixed in control commands are dangerous. In addition to this shell trick, another example would be HTML, where you have to be careful to not let raw HTML data through your guestbook messages so that visitors can't inject HTML into the messages.

With competent and careful system administrators you can avoid problems, but it's still kind of a fragile design in my opinion.

Re:If only this was a Microsoft issue.

[TheDarkMaster]

Humans beings use spaces in the names they give to things or to other human beings. So, why their computers would have to behave differently?