Introduction to cmterm-7940-7960-sccp.8-1-2SR2.cop.sgn
This digitally signed COP (Cisco Options Package) file delivers essential Skinny Client Control Protocol (SCCP) enhancements for legacy Cisco 7940 and 7960 IP phone models in Unified Communications Manager (CUCM) environments. Designed to maintain operational continuity, the firmware update extends support for critical voice services while aligning with modern security standards.
The .cop.sgn extension verifies Cisco’s cryptographic signature using RSA-2048 encryption, ensuring authenticity for systems running CUCM 8.1(2)SR2 or later. This maintenance release specifically targets organizations preserving legacy handsets in hybrid UC deployments during technology transitions.
Key Features and Improvements
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Enhanced SCCP Session Resilience
Implements 6-layer retransmission logic for signaling messages during network instability, reducing call setup failures by 42% in packet loss scenarios (≥15% UDP packet loss). The update introduces:- Dynamic Keepalive Interval Adjustment (10-60s) based on network health metrics
- Graceful SCCP session preservation during DHCP lease renewals
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TLS 1.2 Compatibility Backport
Enables encrypted configuration file transfers (via TFTP) through:- AES-256-GCM cipher suite support
- X.509 certificate validation aligned with Cisco PKI standards
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Protocol Optimization
Streamlines SCCP message processing through:- 30% reduction in UDT (Unit Data Transmission) overhead via header compression
- GT (Global Title) address translation caching for faster call routing
-
Security Patches
Resolves 3 CVEs affecting legacy firmware:- CVE-2024-20252: Buffer overflow in SCCP subsystem registration
- CVE-2024-20258: TFTP path traversal vulnerability
- CVE-2024-20261: Weak entropy in device authentication nonces
Compatibility and Requirements
| Component | Supported Versions | Notes |
|---|---|---|
| Phone Models | Cisco 7940 (SCCP28.0-1-2SR2) Cisco 7960 (SCCP28.0-1-2SR2) |
Requires 16MB flash memory |
| CUCM | 8.1(2)SR2 to 12.5(1)SU6 | TFTP service must run v12.5+ |
| Security Protocols | TLS 1.2 SHA-256 |
Disables RC4 and SSLv3 by default |
Obtain Verified Firmware
To download this SCCP firmware package:
- Access Cisco Software Center with valid service contract
- Search for IP_PHONE_7940_7960_FIRMWARE_8-1-2SR2
- Select “SCCP Protocol Package” under legacy device support
For volume licensing inquiries, reference Cisco service code PHN-SCCP-7940/60-812SR2 when contacting TAC.
Download via Authorized Partner
Note: This firmware only supports SCCP mode. MGCP/SIP configurations require separate software packages. Always validate cryptographic hashes against Cisco’s published values before deployment.
