It was discovered that original upstream patch for server-side command execution flaw affecting setups with map_yp_alias username map enabled did not address the issue completely, due to incorrect use of quoting (backticks vs. single quotes). Code execution was still possible in upstream version 1.4.18.
Issue was fixed upstream in 1.4.19.
Updated upstream security advisory:
Full upstream patch:
This problem did not affect squirrelmail packages as shipped in Red Hat Enterprise Linux 3, 4, and 5. Fix for CVE-2009-1579 has not been released yet, correct patch will be used in the future updates.
squirrelmail-1.4.19-1.fc11 has been submitted as an update for Fedora 11.
squirrelmail-1.4.19-1.fc10 has been submitted as an update for Fedora 10.
squirrelmail-1.4.19-1.fc9 has been submitted as an update for Fedora 9.
The map_yp_alias function in functions/imap_general.php in
SquirrelMail before 1.4.19-1 on Debian GNU/Linux, and possibly other
operating systems and versions, allows remote attackers to execute
arbitrary commands via shell metacharacters in a username string that
is used by the ypmatch program. NOTE: this issue exists because of an
incomplete fix for CVE-2009-1579.
squirrelmail-1.4.19-1.fc9 has been pushed to the Fedora 9 stable repository. If problems still persist, please make note of it in this bug report.
squirrelmail-1.4.19-1.fc10 has been pushed to the Fedora 10 stable repository. If problems still persist, please make note of it in this bug report.
This issue was addressed in:
squirrelmail-1.4.19-2.fc11 has been submitted as an update for Fedora 11.