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Blacklisted by Cyber Patrol

December 22, 1997 - The Censorware Project, a newly formed organization founded by net activists and writers, today announced the release of its report, "Blacklisted by Cyber Patrol: From Ada to Yoyo."

Censorware Project - Exposing the secrets of censorware since 1997


Cyber Patrol is software to filter the internet and block content based on one or more categories: nudity, alcohol, etc.

Software of this type is used not for people to protect themselves, but for authority figures to control what others may view. Cyber Patrol targets many markets: businesses, schools, proxy servers, and even governments. (Cyber Patrol partners with Prodigy to provide censored internet access to China.) Because of this, it has earned the epithet "Censorware."

Software of this type is used not for people to protect themselves, but for authority figures to control what others may view.

The report takes a close look at over 100 sites blocked by the highly-regarded web filtering software from MicroSystems (a subsidiary of The Learning Company). Education Software, HomeSchool Software "The Learning Company is one of the most trusted education software companies for homeschool parents, homeschool teachers, Educators and teachers."

Previous reports about the accuracy of Cyber Patrol have brought to light some blocks of sites which can be called inappropriate at best. "From Ada to Yoyo" presents many more bad blocks, but the report also takes an in-depth look at special topics: the blocking of internet service providers; of gay sites, including a neighborhood with over 20,000 users; of newsgroups; and the subject of whether such a product is appropriate to censor what adults may see in public libraries. 

"I was stunned by some of the sites which were blocked," said Jamie McCarthy, a Michigan-based software developer who is a founder of the Censorware Project and author of the report. "Some of the errors at least made sense: there were pages which could be mistaken for explicit material, even though they were not. 

"But some were bizarre. The town of Ada, Michigan is just an hour's drive from my house: it has a website about local politics, which is blocked as containing full frontal nudity and sexual acts. It's baffling."

"We have only scratched the surface in this report of the problems with CyberPatrol," said James S. Tyre, a free speech attorney in Pasadena, California. "Products as riddled with flaws as CyberPatrol have no business in public libraries, which are arms of the government. Libraries exist to promote knowledge and ideas, but CyberPatrol's bad blocks and reblocks of sites it said would be unblocked demonstrate vividly that its agenda is not to promote the free flow of ideas." 

The Censorware Project's mission is to call public attention to the flaws of blocking software and its inappropriateness in public institutions such as libraries. For more information, pleasecontact Jamie McCarthy at


Reverse engineered by youth rights activists

March 11, 2000
Cyber Patrol(R) 4, a "censorware" product intended to prevent users from accessing undesirable Internet content, has been reverse engineered by youth rights activists Eddy L O Jansson and Matthew Skala. A detailed report of their findings, titled "The Breaking of Cyber Patrol(R) 4", with commentary on the reverse engineering process and cryptographic attacks against the product's authentication system, has been posted on the World Wide Web at this address:

The abstract of the report:

Several attacks are presented on the "sophisticated anti-hacker security" features of Cyber Patrol(R) 4, a "censorware" product intended to prevent users from accessing Internet content considered harmful.
Motivations, tools, and methods are discussed for reverse engineering in general and reverse engineering of censorware in particular. The encryption of the configuration and data files is reversed, as are the password hash functions. File formats are documented, with commentary.
Excerpts from the list of blocked sites are presented and commented upon. A package of source code and binaries implementing the attacks is included.

Eddy L O Jansson

Matthew Skala



censorware vs. privacy & anonymity | Filters Cyber Patrol , Net Nanny, blacklisted, gator


SECURITY: Censorware Companies and Saudi Arabia / China Censorship How to disable your blocking software  The Chinese government is using a new internet content management system named the "Night Crawler System" (pa chong) to block access to websites that have not been registered with authorities. Analysis

SECURITY: A History of Censorship

CENSORSHIP on the Internet  page 2

What CyberPatrol doesn't want you to see

Date: Sat, 11 Mar 2000 09:15:44 -0800 (PST)
From: Declan McCullagh

So I took a look through the CyberNOT list and was pleasantly unsurprised by the program's zaniness, idiocy, and sheer lunacy. Incompetence and prudishness are still alive and well in the censorware industry!

To be fair to CyberPatrol, the bulk of the verboten-links are sexually explicit, or at least may have been at some point in the last five years. But parents and libraries might want to think twice about installing something that can't tell a quilting club from

For instance, CyberPatrol blocks all student organizations at Carnegie Mellon University, including (you guessed it) the Carnegie Threads quilting club, ultimate frisbee, volleyball, and robotics clubs: (Sexual Acts / Text, Intolerance)

For no apparent reason, it blocks the entire corporate site of Golden West Companies ("serving the communications needs of South Dakotans for over 40 years"):

What Usenet newsgroups Cyberpatrol's morality crusaders find objectionable is arguably even more interesting. For instance, journalism discussions are off-limits because of "intolerance," which might be a just criticism of some corners of the industry, but certainly doesn't seem enough to ban discussions of newsgathering:


Some others include discussions of Philip K. Dick's science fiction
(alt.books.phil-k-dick is sorted into drug/drug culture), feminism, Jungian psychology, food, Chinese culture, and chess and bridge.

More info:


ba.motss (same-sex issues and discussions)