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How Poor Punctuation Can Break Windows
An anonymous reader writes with a report at Ars Technica about how a small bug can lead to a security problem. In this case, the problem is that quotation marks — or the lack of them — can be significant. From the Ars article:
"The scenario... requires a 'standard' user with access rights to create a directory to a fileserver and an administrator executing a vulnerable script," Frank Lycops and Raf Cox, security researchers with The Security Factory, said in an e-mail interview. "This allows the attacker to gain the privileges of the user running the script, thus becoming an administrator." While the attack falls short of the severity of the Shellshock family of Linux shell vulnerabilities, the two researchers stressed that it's a good example of how untrusted input can be used to execute commands on a system. The researchers identified at least one popular script with the vulnerability. When the script attempts to set the starting directory for system administration work, it inadvertently runs the command appended to the malicious directory's name as well. ... The solution is to use proper coding practices—in this case, the judicious use of quotation marks. Quotation marks are used in the shell environment to make sure that the data inside the quotes is not interpreted by the program as a command.
On the other hand you could do much worse on Linux using Bash to remotely gain control to a system with no administrator action required.
... but it was patched in under a week. The sysadmins who haven't applied the patches (which didn't require a reboot, or even so much as reloading the shell after installation) are the same ones who run Windows boxes so far behind on patches they're still remotely exploitable, too. Hell, they probably run Apache on Cygwin on Windows and never patched that, making their Windows box vulnerable to Shellshock. That's possible because, guess what, Bash isn't Linux and, in fact, predates Linux; Bash runs on *every* OS. Yes, even the iPhone can run Bash if you jailbreak it.
For the record, Yahoo, running FreeBSD, was compromised via Shellshock. Apple's Darwin kernel, which both OSX and iOS run on top of, was forked from the very same kernel Yahoo's servers run, and yes, OSX Yosemite is still waiting for a patch for Heartbleed, which means I have to keep a large number of services I'd like to be running disabled for the time being. My Linux servers, though, were all patched within hours; when an alternate exploit was found, they were once again patched in hours. I'm not even sure the Windows POSIX layers have released patched builds yet, so at this point Windows systems are more vulnerable to this than anything other production system (Yodsemite is still in beta, remember); fortunately, I don't run a POSIX layer on my Windows dev box.
APK quotes people (including myself) without context and should not be trusted. Just thought you should know.
Except in the cases it triggers the exploit. IMHO, that's the newsworthy bit of this.
Not quoting causes issues is news along the same level as "water is wet". Trying to be secure and breaking things? That's big. At least it's not possible with filenames.