12-02-2011, 11:20 PM
(12-02-2011, 12:53 PM)nandolu21 Wrote: I did not understand me explain better!they(cisco and your isp) issued a patch to stop you forcing a config
http://www.cisco.com/en/US/products/prod...4e97.shtml
A defect in Cisco IOS Software for the uBR7200 and uBR7100 series Universal Broadband Routers causes the MD5 test to be skipped if an MIC is not provided in the DOCSIS configuration file. A DOCSIS configuration can be modified with a hex editor to truncate the file just before the MIC and adjust other fields to produce an invalid configuration file that will be accepted by the cable modem and the CMTS. When the cable modem attempts to register, a vulnerable CMTS fails to challenge the missing MIC and allows the cable modem to come on line. Using this vulnerability, the range of possible configurations is no longer restricted to a small alternative set for the same service provider; a completely custom configuration can be generated in which all of the options can be specified. This defect is documented as CSCdx72740, and details are available to registered users of the Cisco website.
The Cisco IOS Software configuration command cable tftp-enforce prohibits a cable modem from registering and coming on line if there is no matching TFTP traffic through the CMTS preceding the registration attempt. This feature has been introduced via CSCdx57688 and can be viewed by registered users of the Cisco website. This new command is available on the uBR10012 router as well as the uBR7200 and uBR7100 series.
Both the cable tftp-enforce command feature and the fix for the MD5 authentication bypass are necessary to properly mitigate these vulnerabilities, and Cisco is making fixed software available as shown below.
Some non-Cisco cable modems may be running older versions of software that save a local copy of the configuration information and use that cached copy at registration time instead of obtaining the actual file from a TFTP server. In addition to the possibility that the cable modem is not using the proper configuration information, the cable modem's user may be mistakenly accused of attempting theft of service.
__________________________________________________________________________________
******new discord chat linkĀ https://discord.gg/5BQQbsb*******
******new discord chat linkĀ https://discord.gg/5BQQbsb*******