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Finance industry faces serious IT security issues

23rd June 2008 The finance industry needs to keep its eye on the small change as well as the bigger picture of its security vulnerabilities Read More

Retail sector faces serious IT security issues

23rd June 2008 The retail sector needs to set out its stall and ring the changes in its security vulnerabilities if it is to avoid the potential for hackers to gain unauthorised system access and disrupt service availability Read More

IT managers have more security headaches to deal with

11th May 2008 NTA Monitor's 2008 Annual Security Report has revealed that the average number of vulnerabilities found per test have increased to 21 compared with 19 in 2007 Read More

Solutions not excuses for patch management warns NTA Monitor

23rd April 2008 Patch management is a vital security requirement for any organsation Read More

Borderware Firewall Flaw

NTA Monitor, Internet security testing specialists, through routinely testing large numbers of corporate customer sites, have discovered a flaw in the design of Borderware, which means it is vulnerable to TCP/IP session spoofing.

Borderware, a firewall product of some years pedigree and a market share of about 10%, formerly a product of Secure Computing Inc, has recently become a product of Borderware Technologies Inc.

In the UK the product has been used by numbers of health organisations in the NHS, and local government.

The root cause of the flaw is that the TCP/IP stack in the product allocates initial TCP sequence numbers in a non-random, predictable manner.

The vulnerability is not trivial to exploit, but where IP addressing is used as part of an authentication scheme the implications could be serious. Simpler exploitation avenues could include untraceable 'perfect spoofing' of email.

NTA Monitor have shown that Version 5 is vulnerable; and since being informed Borderware have made their own tests and confirmed the vulnerability, which is also assumed to apply to previous versions.

Borderware have as yet made no public statement, but have said in email that the next version will address the problem.

The firewall has it's own operating system built in (a BSD Unix variant), and thus it is not possible for end-users to patch the operating system themselves.

This advisory was first released on 1st September 1998.

References

  • Security Mailing list discussions
  • NTA Monitor post and following thread on 'Bugtraq'
  • Mailing list post - Summary of emails and comments received
  • IP-spoof general references and history
  • Security Problems in the TCP/IP Protocol Suite Steve Bellovin, 1989, (compressed PostScript)
  • A Weakness in the 4.2BSD UNIX TCP/IP software Robert Morris, 1985, (compressed PostScript)
  • Steve Bellovin's description of TCP SEQ attacks
  • Details of how Kevin Mitnick used TCP SEQ attack
  • 1995 CERT Advisory CA-95:01
  • IP-Spoofing attacks reported
  • 1996 CERT Advisory CA-96:21
  • Syn flooding atacks reported
  • IP Spoofing explained (hacker article)