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Skype Can't Fix a Nasty Security Bug Without a Massive Code Rewrite (zdnet.com)
ZDNet reports of a security flaw in Skype's updater process that "can allow an attacker to gain system-level privileges to a vulnerable computer." If the bug is exploited, it "can escalate a local unprivileged user to the full 'system' level rights -- granting them access to every corner of the operating system." What's worse is that Microsoft, which owns Skype, won't fix the flaw because it would require the updater to go through "a large code revision." Instead, Microsoft is putting all its resources on building an altogether new client. From the report: Security researcher Stefan Kanthak found that the Skype update installer could be exploited with a DLL hijacking technique, which allows an attacker to trick an application into drawing malicious code instead of the correct library. An attacker can download a malicious DLL into a user-accessible temporary folder and rename it to an existing DLL that can be modified by an unprivileged user, like UXTheme.dll. The bug works because the malicious DLL is found first when the app searches for the DLL it needs. Once installed, Skype uses its own built-in updater to keep the software up to date. When that updater runs, it uses another executable file to run the update, which is vulnerable to the hijacking. The attack reads on the clunky side, but Kanthak told ZDNet in an email that the attack could be easily weaponized. He explained, providing two command line examples, how a script or malware could remotely transfer a malicious DLL into that temporary folder.
The article indicates that the Updater is the problem, not Skype. The Updater runs in a privileged environment, and is susceptible to loading non-system DLLs. The article says the same can happen on Macs and on Linux except that neither platform uses DLLs nor allows sourcing libraries from local (no-system) directories.
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That way you can be kinda sorta sure the entire thing came from Microsoft, maybe...
“He’s not deformed, he’s just drunk!”
Just look at the stats. Failing Linux has had hundreds of CVE's in just the last year with a lot more and worse severities than all the current versions of amazing Windows *combined*. If you want to trust your computer to be secure, you are better off with Windows than littul linux. It's a simple fact, easily proven, but completely politically incorrect to say here which is everyone knows it is true.
While officially Microsoft supports static linking, in practice, it is necessary to use DLLs in many situations. The Microsoft official answer is at: Extension DLLs
The practical reasons that I have been forced to use DLLs are:
Last I checked, Skype was entirely optional to install, something you have to go out of your way to infect your system with, not something Microsoft jams down anyone's throat.
When WIndows 8 came out, Skype was there by default. It also happened to be extra retarded by default. I remember it because some friends asked me to help them log in to the Skype app on a new Windows 8 machine. After some swearing and Googling, I discovered that the app bundled with Windows will only work with a Windows Live account, Skype logins that existed before the MS infection required that I uninstall the bundled version and get the less retarded version from Skype.com
What's worse is that Microsoft, which owns Skype, won't fix the flaw because it would require the updater to go through "a large code revision." Instead, Microsoft is putting all its resources on building an altogether new client.
Man I gotta hand it to whomever at Microsoft actually convinced their boss to go this route. There was a MSN messenger once, you know, Microsoft's IM client, they dumped it and bought Skype. Now they're dumping Skype for inhouse MSN messenger 2.0? Hahahahaha nice job.