Field reports describe internet bots sending SIP INVITE and OPTIONS to Expressway-E at around 2 to 3 per second, trying varied called patterns to find a PSTN route and spoofing the organisation's own domain or the Expressway IP as caller.

field report · Checked 2026-09-25

Vendor
Cisco
Product
Cisco Expressway
Subsystem
security
Deployment
on-premises
Region
not restricted
Release range
unspecified
Status
field report
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Expressway business-to-business calling: source note expressway-b2b-calling-field-bot-scanning. WarmTransfer. https://warmtransfer.net/knowledge/claims/expressway-b2b-calling-field-bot-scanning

BibTeX

@misc{warmtransfer-claim-expressway-b2b-calling-field-bot-scanning,
  title  = {Expressway business-to-business calling: source note expressway-b2b-calling-field-bot-scanning},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/expressway-b2b-calling-field-bot-scanning},
  note   = {Source note expressway-b2b-calling-field-bot-scanning, checked 2026-09-25}
}

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