Question is: What app causes it and why setroubleshoot doesn't show the app name?

Summary:

SELinux is preventing 466F746F6C616220466F746F737665 from making the program
stack executable.

Detailed Description:

[SELinux is in permissive mode. This access was not denied.]

The 466F746F6C616220466F746F737665 application attempted to make its stack
executable. This is a potential security problem. This should never ever be
necessary. Stack memory is not executable on most OSes these days and this will
not change. Executable stack memory is one of the biggest security problems. An
execstack error might in fact be most likely raised by malicious code.
Applications are sometimes coded incorrectly and request this permission. The
SELinux Memory Protection Tests
(http://people.redhat.com/drepper/selinux-mem.html) web page explains how to
remove this requirement. If 466F746F6C616220466F746F737665 does not work and you
need it to work, you can configure SELinux temporarily to allow this access
until the application is fixed. Please file a bug report.

Allowing Access:

Sometimes a library is accidentally marked with the execstack flag, if you find
a library with this flag you can clear it with the execstack -c LIBRARY_PATH.
Then retry your application. If the app continues to not work, you can turn the
flag back on with execstack -s LIBRARY_PATH. Otherwise, if you trust
466F746F6C616220466F746F737665 to run correctly, you can change the context of
the executable to execmem_exec_t. "chcon -t execmem_exec_t
'466F746F6C616220466F746F737665'" You must also change the default file context
files on the system in order to preserve them even on a full relabel. "semanage
fcontext -a -t execmem_exec_t '466F746F6C616220466F746F737665'"

Fix Command:

chcon -t execmem_exec_t '466F746F6C616220466F746F737665'

Additional Information:

Source Context                unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1
                              023
Target Context                unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1
                              023
Target Objects                None [ process ]
Source                        466F746F6C616220466F746F737665
Source Path                   466F746F6C616220466F746F737665
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           
Target RPM Packages           
Policy RPM                    selinux-policy-3.6.32-46.fc12
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Permissive
Plugin Name                   allow_execstack
Host Name                     (removed)
Platform                      Linux dhcp-lab-172.englab.brq.redhat.com
                              2.6.31.5-127.fc12.i686.PAE #1 SMP Sat Nov 7
                              21:25:57 EST 2009 i686 i686
Alert Count                   2
First Seen                    Fri 27 Nov 2009 09:31:53 PM CET
Last Seen                     Fri 27 Nov 2009 09:32:25 PM CET
Local ID                      a812528f-644b-4953-9fe9-57344df73b6a
Line Numbers                  

Raw Audit Messages            

node=dhcp-lab-172.englab.brq.redhat.com type=AVC msg=audit(1259353945.372:21179): avc:  denied  { execstack } for  pid=2327 comm=466F746F6C616220466F746F737665 scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tclass=process



Hash String generated from  selinux-policy-3.6.32-46.fc12,allow_execstack,466F746F6C616220466F746F737665,unconfined_t,unconfined_t,process,execstack
audit2allow suggests:

#============= unconfined_t ==============
allow unconfined_t self:process execstack;