net-snmp -- fixproc insecure temporary file creation

A Gentoo advisory reports:

Net-SNMP creates temporary files in an insecure manner,
possibly allowing the execution of arbitrary code.
A malicious local attacker could exploit a race condition
to change the content of the temporary files before they
are executed by fixproc, possibly leading to the execution
of arbitrary code. A local attacker could also create
symbolic links in the temporary files directory, pointing
to a valid file somewhere on the filesystem. When fixproc
is executed, this would result in the file being
overwritten.