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Security for Private Branch Exchange Systems



David R. Kuhn


This document provides an introduction to security for private branch exchange systems (PBXs). The primary audience is agency system administrators and others responsible for the installation and operation of PBX systems. Major threat classes are explained, common vulnerabilities identified, and countermeasures are suggested to enhance the security of PBXs. Readers are referred to a NIST Special Publication on PBX security for more detailed coverage of the issues.
ITL Bulletin -


computer security, information security, private branch exchange systems (PBXs), telecommunications


Kuhn, D. (2000), Security for Private Branch Exchange Systems, ITL Bulletin, National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 24, 2024)


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Created August 1, 2000, Updated February 19, 2017