Installing new firmware updates the phone-model device default to the new version, and Cisco recommends setting the default back to the previous load if the organisation is not ready to upgrade phones.

Checked 2026-09-25

If you are not prepared to upgrade phones at this time, we recommend that you adjust this value back to the previous firmware load.
Vendor
Cisco
Product
Cisco Unified Communications Manager
Subsystem
Device Defaults
Deployment
on-premises
Region
not restricted
Release range
Release 15 and SUs
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Cisco IP phone firmware management: source note cucm-phone-firmware-default-overwritten. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-phone-firmware-default-overwritten

BibTeX

@misc{warmtransfer-claim-cucm-phone-firmware-default-overwritten,
  title  = {Cisco IP phone firmware management: source note cucm-phone-firmware-default-overwritten},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cucm-phone-firmware-default-overwritten},
  note   = {Source note cucm-phone-firmware-default-overwritten, checked 2026-09-25}
}

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