Mandriva Linux Security Advisory – Tavis Ormandy discovered that sudo does not perform sufficient environment cleaning; in particular the SHELLOPTS and PS4 variables are still passed to the program running as an alternate user which can result in the execution of arbitrary commands as the alternate user when a bash script is executed.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/41056/MDKSA-2005-201.txt
Source: https://packetstormsecurity.com/files/41056/Mandriva-Linux-Security-Advisory-2005.201.html