Source note · Unified CM security hardening
On a fresh install the minimum TLS version is 1.2, with TLS 1.0 and 1.1 disabled. An upgrade or migration keeps the minimum TLS version from the previous release.
Checked 2026-09-25
- Vendor
- Cisco
- Product
- Unified Communications Manager
- Subsystem
- TLS
- Deployment
- on-premises
- Region
- not restricted
- Release range
- 15SU2 and later
- Checked
- 2026-09-25
Sources
- Security Guide for Cisco Unified Communications Manager, Release 15 and SUs - TLS 1.3 Setup (From Release 15SU2 Onwards) — Cisco Systems · tier 2 current vendor documentation · TLS 1.3 Setup > Supported TLS versions (fresh install vs upgrade)
Cite this note
APA
WarmTransfer. (2026, September 25). Unified CM security hardening: source note cucm-security-hardening-tls-fresh-vs-upgrade. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-security-hardening-tls-fresh-vs-upgrade
BibTeX
@misc{warmtransfer-claim-cucm-security-hardening-tls-fresh-vs-upgrade,
title = {Unified CM security hardening: source note cucm-security-hardening-tls-fresh-vs-upgrade},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/cucm-security-hardening-tls-fresh-vs-upgrade},
note = {Source note cucm-security-hardening-tls-fresh-vs-upgrade, checked 2026-09-25}
}