The fail2ban Asterisk filter bans source IPs from Asterisk log lines such as failed registrations for wrong password, username mismatch, no matching peer, or ACL failures, and 'Rejecting unknown SIP connection'.

Checked 2026-09-25

Vendor
fail2ban project
Product
fail2ban asterisk filter
Subsystem
Log indicators
Deployment
on-premises
Region
not restricted
Release range
master branch as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP scanning and telephony denial of service: source note sip-scanning-tdos-fail2ban-registration-failures. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-scanning-tdos-fail2ban-registration-failures

BibTeX

@misc{warmtransfer-claim-sip-scanning-tdos-fail2ban-registration-failures,
  title  = {SIP scanning and telephony denial of service: source note sip-scanning-tdos-fail2ban-registration-failures},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-scanning-tdos-fail2ban-registration-failures},
  note   = {Source note sip-scanning-tdos-fail2ban-registration-failures, checked 2026-09-25}
}

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