Privilege elevation

A number of computer operating systems employ security features to help prevent malicious software from gaining sufficient privileges to compromise the computer system. Operating systems lacking such features, such as DOS, Windows implementations prior to Windows NT (and its descendants), CP/M-80, and all Mac operating systems prior to Mac OS X, had only one category of user who was allowed to do anything. With separate execution contexts it is possible for multiple users to store private files, for multiple users to use a computer at the same time, to protect the system against malicious users, and to protect the system against malicious programs. The first multi-user secure system was Multics, which began development in the 1960s; it wasn't until UNIX, BSD, Linux, and NT in the late 80s and early 90s that multi-tasking security contexts were brought to x86 consumer machines.

A major security consideration is the ability of malicious applications to simulate keystrokes or mouse clicks, thus tricking or spoofing the security feature into granting malicious applications higher privileges.

If either gksudo's "lock" feature or UAC's Secure Desktop were compromised or disabled, malicious applications could gain administrator privileges by using keystroke logging to record the administrator's password; or, in the case of UAC if running as an administrator, spoofing a mouse click on the "Allow" button. For this reason, voice recognition is also prohibited from interacting with the dialog. Note that since gksu password prompt runs without special privileges, malicious applications can still do keystroke logging using e.g. the strace tool. (ptrace was restricted in later kernel versions)

Another security consideration is the ability of malicious software to spoof dialogs that look like legitimate security confirmation requests. If the user were to input credentials into a fake dialog, thinking the dialog was legitimate, the malicious software would then know the user's password. If the Secure Desktop or similar feature were disabled, the malicious software could use that password to gain higher privileges.

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