(RHSA-2011:0261) Low: bash security and bug fix update

Bash (Bourne-again shell) is the default shell for Red Hat Enterprise
Linux.

It was found that certain scripts bundled with the Bash documentation
created temporary files in an insecure way. A malicious, local user could
use this flaw to conduct a symbolic link attack, allowing them to overwrite
the contents of arbitrary files accessible to the victim running the
scripts. (CVE-2008-5374)

This update also fixes the following bugs:

• If a child process’s PID was the same as the PID of a previously ended
  child process, Bash did not wait for that child process. In some cases this
  caused “Resource temporarily unavailable” errors. With this update, Bash
  recycles PIDs and waits for processes with recycled PIDs. (BZ#521134)

• Bash’s built-in “read” command had a memory leak when “read” failed due
  to no input (pipe for stdin). With this update, the memory is correctly
  freed. (BZ#537029)

• Bash did not correctly check for a valid multi-byte string when setting
  the IFS value, causing Bash to crash. With this update, Bash checks the
  multi-byte string and no longer crashes. (BZ#539536)

• Bash incorrectly set locale settings when using the built-in “export”
  command and setting the locale on the same line (for example, with
  “LC_ALL=C export LC_ALL”). With this update, Bash correctly sets locale
  settings. (BZ#539538)

All bash users should upgrade to these updated packages, which contain
backported patches to correct these issues.