Cisco's hardening guide advises keeping silent discard of untrusted requests enabled and using no silent-discard untrusted only when needed.

Checked 2026-09-25

Vendor
Cisco
Product
Cisco Unified Border Element (CUBE)
Subsystem
Hardening - toll fraud
Deployment
on-premises
Region
not restricted
Release range
as of 2023-04-10
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-harden-keep-silent-discard. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-scanning-tdos-harden-keep-silent-discard

BibTeX

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

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