1. Ubuntu Security Notices
  2. USN-72-1

USN-72-1: Perl vulnerabilities

Publication date

2 February 2005

Overview

Perl vulnerabilities

Releases

Details

Two exploitable vulnerabilities involving setuid-enabled perl scripts
have been discovered. The package “perl-suid” provides a wrapper
around perl which allows to use setuid-root perl scripts, i.e.
user-callable Perl scripts which have full root privileges.

Previous versions allowed users to overwrite arbitrary files by
setting the PERLIO_DEBUG environment variable and calling an arbitrary
setuid-root perl script. The file that PERLIO_DEBUG points to was then
overwritten by Perl debug messages. This did not allow precise control
over the file content, but could destroy important data. PERLIO_DEBUG
is now ignored for setuid scripts. (CAN-2005-0155)

In addition, calling a setuid-root perl script with a very long path
caused a buffer overflow if PERLIO_DEBUG was set. This buffer overflow
could be exploited to execute arbitrary files with full root
privileges. (CAN-2005-0156)

Two exploitable vulnerabilities involving setuid-enabled perl scripts
have been discovered. The package “perl-suid” provides a wrapper
around perl which allows to use setuid-root perl scripts, i.e.
user-callable Perl scripts which have full root privileges.

Previous versions allowed users to overwrite arbitrary files by
setting the PERLIO_DEBUG environment variable and calling an arbitrary
setuid-root perl script. The file that PERLIO_DEBUG points to was then
overwritten by Perl debug messages. This did not allow precise control
over the file content, but could destroy important data. PERLIO_DEBUG
is now ignored for setuid scripts. (CAN-2005-0155)

In addition, calling a setuid-root perl script with a very long path
caused a buffer overflow if PERLIO_DEBUG was set. This buffer overflow
could be exploited to execute arbitrary files with full root
privileges. (CAN-2005-0156)

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
4.10 warty perl – 

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References

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