Thanks for the report. Please have a look at
https://en.opensuse.org/openSUSE:Bugreport_SELinux
and provide the information that is listed there. Thanks

Additional information:

# Operating System:

openSUSE MicroOS Desktop (openSUSE Aeon)

# SELinux status, mode and policy name

SELinux status:                 enabled
SELinuxfs mount:                /sys/fs/selinux
SELinux root directory:         /etc/selinux
Loaded policy name:             targeted
Current mode:                   enforcing
Mode from config file:          enforcing
Policy MLS status:              enabled
Policy deny_unknown status:     allowed
Memory protection checking:     actual (secure)
Max kernel policy version:      33

# SELinux policy version and repository:
Information for package selinux-policy:
---------------------------------------
Repository     : openSUSE-Tumbleweed-Oss
Name           : selinux-policy
Version        : 20231030-1.1
Arch           : noarch
Vendor         : openSUSE
Installed Size : 24.8 KiB
Installed      : Yes (automatically)
Status         : up-to-date
Source package : selinux-policy-20231030-1.1.src
Upstream URL   : https://github.com/fedora-selinux/selinux-policy.git
Summary        : SELinux policy configuration
Description    : 
    SELinux Reference Policy. A complete SELinux policy that can be used
    as the system policy for a variety of systems and used as the basis for
    creating other policies.

# The software (incl. version) that is affected by the SELinux issue and the error message

run the following command in the a distrobox container

`dbus-send --system --print-reply --dest=org.freedesktop.Avahi  /org/freedesktop/DBus org.freedesktop.DBus.Peer.Ping` 

Error:
```
org.freedesktop.DBus.Error.NoReply: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.

# SELinux Audit log

sudo ausearch -ts today -m USER_AVC
----
time->Wed Nov 15 13:18:31 2023
type=USER_AVC msg=audit(1700072311.494:127): pid=1037 uid=484 auid=4294967295 ses=4294967295 subj=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023 msg='avc:  denied  { send_msg } for msgtype=method_return dest=:1.139 spid=1034 tpid=6336 scontext=system_u:system_r:avahi_t:s0 tcontext=unconfined_u:unconfined_r:container_runtime_t:s0 tclass=dbus permissive=0 exe="/usr/bin/dbus-daemon" sauid=484 hostname=? addr=? terminal=?'

# The exact steps how to configure and use the system to trigger the AVC

Run the command above in a distrobox container

Not an Aeon bug - distrobox and SELinux is more generic than that, assigning to Tumbleweed/SELinux

Hi, 
sorry for the long delay, but after trying different approaches I could not reproduce the issue. I have openSUSE Aeon with selinux policy version 20231124-1.1 (current version, newer than yours). Then i did this:

test@localhost:~> distrobox create -n test
...
test@localhost:~> distrobox enter test
Starting container...                   	 [ OK ]
...
(inside the container)
test@test:~> sudo mkdir /run/dbus
test@test:~> sudo ln -s  /run/host/run/dbus/system_bus_socket  /run/dbus/system_bus_socket
test@test:~> dbus-send --system --print-reply --dest=org.freedesktop.Avahi  /org/freedesktop/DBus org.freedesktop.DBus.Peer.Ping
method return time=1702048240.291599 sender=:1.2 -> destination=:1.167 serial=38 reply_serial=2
test@test:~> exit
logout
test@localhost:~> sudo ausearch -m avc -ts today
[sudo] password for test: 
<no matches>

Also, I did another setup with a distrobox container created with --init and the dbus-send still works for me. Also tried it with different images, e.g. tumbleweed:latest, no issue.

We did quite some big changes in the last selinux-policy update, could you please check if updating fixes it for you?
If it does not, could you please share:
- how did you set up the dbus socket in the container? 
- did you provide more arguments when creating the distrobox container or have something in your config that could cause this?

Thanks a lot :)

I will close this, as I can not reproduce the issue. Please feel free to reopen if the issue persists :)