Cisco states that it is continuously adding infrastructure to the Webex cloud so that listing allowed IP addresses is not practical, and that the shared-secret signature is the technique it introduced to let a receiver verify cryptographically that a request came from Cisco.

Checked 2026-09-16

Vendor
Cisco
Product
Webex Calling
Subsystem
Webhooks
Deployment
not restricted
Region
not restricted
Release range
not restricted
Checked
2026-09-16

Sources

Cite this note

APA

WarmTransfer. (2026, September 16). What a Webex webhook guarantees: source note wxwh-why-there-is-no-ip-allowlist. WarmTransfer. https://warmtransfer.net/knowledge/claims/wxwh-why-there-is-no-ip-allowlist

BibTeX

@misc{warmtransfer-claim-wxwh-why-there-is-no-ip-allowlist,
  title  = {What a Webex webhook guarantees: source note wxwh-why-there-is-no-ip-allowlist},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/wxwh-why-there-is-no-ip-allowlist},
  note   = {Source note wxwh-why-there-is-no-ip-allowlist, checked 2026-09-16}
}

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