sudo -- Secure path vulnerability
Todd Miller reports:
Most versions of the C library function getenv() return the
first instance of an environment variable to the caller. However,
some programs, notably the GNU Bourne Again SHell (bash), do
their own environment parsing and may choose the last instance
of a variable rather than the first one.
An attacker may manipulate the environment of the process that
executes Sudo such that a second PATH variable is present. When
Sudo runs a bash script, it is this second PATH variable that
is used by bash, regardless of whether or not Sudo has overwritten
the first instance of PATH. This may allow an attacker to
subvert the program being run under Sudo and execute commands
he/she would not otherwise be allowed to run.
Copyright © 2003-2005 Jacques Vidrine and contributors.
Please see the source of this document for full copyright