secure_sid_scripts(5) File Formats Manual secure_sid_scripts(5)
secure_sid_scripts - controls whether setuid and setgid bits on scripts are honored
This tunable controls whether and bits on executable scripts have any effect. Honoring on scripts make a system vulnerable to attack by
The default value for this variable is 1, indicating that bits are to be ignored by the execve(2) system call for higher security. The
tunable can be set to 0 for a compatibility with older releases at the expense of security. Hewlett-Packard strongly recommends that you
not change the value of this tunable unless there is an urgent need to do so.
When a script with bits is executed, the kernel generates the following error message to both the terminal controlling and the system log.
(To view the error message, use dmesg(1M) or inspect
Who is Expected to Change This Tunable?
Restrictions on Changing
Changes to this tunable take effect for new scripts started after the change.
When Should the Value of This Tunable Be Changed?
This tunable controls operational modes rather than data structure sizes and limits. The appropriate setting for a system depends on
whether you consider security or compatibility to be most important.
A value of is compatible with previous releases of HP-UX, but it is also less secure.
A value of provides security against race condition attacks exploiting scripts.
What Are the Side Effects of Changing the Value
This tunable controls only executable scripts (not programs) with bit set. HP-UX does not ship with any such scripts. If the customer
wishes to use scripts, third party applications such as or can be used. Alternatively, the shell script can be wrapped in a simple C pro-
gram that runs the shell script with appropriate permissions:
What Other Tunable Values Should Be Changed at the Same Time?
None. All HP-UX kernel tunable parameters are release specific. This parameter may be removed or have its meaning changed in future
releases of HP-UX.
Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parameter values. After installation,
some tunable parameters may no longer be at the default or recommended values. For information about the effects of installation on tun-
able values, consult the documentation for the kernel software being installed. For information about optional kernel software that was
factory installed on your system, see at
was developed by HP.
chmod(1), execve(2), kctune(1M).
Tunable Kernel Parameters secure_sid_scripts(5)