Hello, no change has been done in firewall in the last few weeks.

Attached is the show tec

Something wrong in the config.

Can you post the ''sh run'' from the PIX?

If you're not using PDM you might as well disable it, otherwise let's see what's wrong with the configuration.

Federico.

Do you use PDM???

Otherwise, we can disable PDM and see if the problem goes away:

PIX(config)# no http server enable

If you use PDM, then we need to figure out who is PDM trying to communicate with...

Something changed when the problem started?

Can you access the PIX via PDM fine?

Federico.

As said before the problem happens even if PDM is not been used.

The main problem is that the pix is hanging at least once a day. While the problem is not happening I can access the PDM.

The PIX could be hanging due to several reasons.
For example, I would remove this command:
logging console debugging
This will explain that everything comes back to normal when you reboot the PIX.
You get that error because you're logging PDM events:
pdm logging debugging 512

Sometimes what we have done is to lower the xlate and conn timeouts:
timeout xlate 00:10:00
timeout conn 00:05:00

As a recommendation, connect a syslog server and send the logs to the server, with the correct timestamp to check
what's the status of the PIX when it hangs.

Federico.