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Cisco Bug: CSCun17651 - 78X1 unregisters due to malformed From header in keepalive message

Last Modified

Mar 06, 2018

Products (4)

  • Cisco IP Phone 7800 Series
  • Cisco IP Phone 7841
  • Cisco IP Phone 7821
  • Cisco IP Phone 7861

Known Affected Releases


Description (partial)

7821/7841/7861 model phones sends malformed "From" field in keepalive which causes the phone to unregister.

Intermittently, these model phones will unregister and will not re-register until they are manually rebooted.

The phone will start sending a From field in the register packets that looks like "From: XXXX" where XXXX is the DN of the phone.

When this happens, CUCM will apply with the following SIP message:
SIP/2.0 400 Bad Request - 'Malformed/Missing FROM: field' 

The correct formatting of the From header should be:
From: <sip:XXXX@Y.Y.Y.Y>;tag=885a92d9942a11e8410069db-3e4f7947

Related Community Discussions

<key>CSCun17651</key> - 78X1 unregisters due to malformed From header in keepalive message - 1
Is it possible this is part of the same issue based on the reason for out of service code 14 it displays ?      [07:43:37am,03/26/18] DeviceName=SEPCC98914FA699 DeviceIPv4Address= IPv4DefaultGateway= DeviceIPv6Address= IPv6DefaultGateway= ModelNumber=CP-7821 NeighborIPv4Address= NeighborIPv6Address= NeighborDeviceID=   NeighborPortID= DHCPv4Status=1 DHCPv6Status=3 TFTPCfgStatus=1 DNSStatusUnifiedCM1=1 DNSStatusUnifiedCM2=1 DNSStatusUnifiedCM3=1 DNSv6StatusUnifiedCM1=0 ...
Latest activity: Mar 28, 2018
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