It is possible I be attacked for my analog FXO line?

Hi,

I use Asterisk in my Ubuntu, and I’m received all time outgoing in my FXO Dahdi

see in my CLI

-- Starting simple switch on 'DAHDI/2-1'
    -- Executing [s@URA2:1] Answer("DAHDI/2-1", "") in new stack
    -- Executing [s@URA2:2] GotoIfTime("DAHDI/2-1", "07:30-17:50,mon-fri,*,*?expediente") in new stack
    -- Goto (URA2,s,9)
    -- Executing [s@URA2:9] Wait("DAHDI/2-1", "1") in new stack
    -- Executing [s@URA2:10] Set("DAHDI/2-1", "CONTA=1") in new stack
    -- Executing [s@URA2:11] Set("DAHDI/2-1", "TIMEOUT(digit)=1") in new stack
    -- Digit timeout set to 1.000
    -- Executing [s@URA2:12] Set("DAHDI/2-1", "TIMEOUT(response)=4") in new stack
    -- Response timeout set to 4.000
    -- Executing [s@URA2:13] BackGround("DAHDI/2-1", "/var/lib/asterisk/sounds/escritorio") in new stack
    -- <DAHDI/2-1> Playing '/var/lib/asterisk/sounds/escritorio.gsm' (language 'en')
    -- Executing [s@URA2:14] BackGround("DAHDI/2-1", "beep") in new stack
    -- <DAHDI/2-1> Playing 'beep.gsm' (language 'en')
    -- Executing [s@URA2:15] WaitExten("DAHDI/2-1", "8") in new stack
    -- Timeout on DAHDI/2-1, going to 't'
    -- Executing [t@URA2:1] Dial("DAHDI/2-1", "SIP/2051,60,tT") in new stack
  == Using SIP RTP CoS mark 5
    -- Called SIP/2051
    -- SIP/2051-00004714 is ringing
    -- SIP/2051-00004714 answered DAHDI/2-1
       > 0x28af130 -- Probation passed - setting RTP source address to 192.2.1.50:18396
    == Using SIP RTP CoS mark 5 
  == Spawn extension (URA2, t, 1) exited non-zero on 'DAHDI/2-1'
    -- Hanging up on 'DAHDI/2-1'
    -- Hungup 'DAHDI/2-1'

When I answer the call, the connection goes dead and drops the connection. And I have to Hungup it.

I may have suffered an attack on my Asterisk?

Yes. If you have a dialplan that allows it.

Ok, what I have to do now?

Build a dialplan that doesn’t allow unauthorized users to dial out your FXO lines…

Ok, but how can I fix this problem? I have to reset my Asterisk?