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Anonymous
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SIP stack timer retransmit

I am seeing this "SIP stack timer retransmit" every now and then in the log. Also I see this suspicious ip address that when I googled showed the following details:

5.62.63.182   --> Avast

212.129.10.158 --> Some ip in France described as in abuseipdb.com

I restricted both the ip with a subnet on my firewall but I still see these in the adtran logs. Any help is really appreciated.

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jayh
Honored Contributor
Honored Contributor

Re: SIP stack timer retransmit

Your firewall probably doesn't apply it to the "self" context, so it blocks traffic through the device but not to the device. Firewalling these attackers individually doesn't scale very well.

Fix:

Create a standard access-list sip-access. include in it the IPs of the external SIP servers of your provider(s) as well as any internal subnets with SIP phones

Apply it to the SIP process.

ip access-list standard sip-access

permit 192.168.2.0 0.0.0.255 ! internal phone subnet

permit host 192.0.2.33  ! Provider's SIP server

!

sip access-class ip "sip-access" in