TOM-Skype Q & A

作者:Nart Villeneuve    来源:Internet Censorship Explorer

I have been getting a lot of questions and feedback on the "Breaching Trust" report. I'll try to post more details and answer questions. Here are some of the common questions people have been asking.

How were you able to determine that messages containing keywords were being uploaded to a web server? How did you find and decrypt the messages?

Wireshark. Every time I typed the word "fuck" an HTTP connection was made to a TOM Skype server. I visited the URL directly in Firefox, cut off the file name and was able to view the contents of the directory. With a little poking around I found the encryption key. A few lines of Python and voila. I did not "crack" anything nor was there any "elite" hackery — just plain, simple stuff.

Is "normal" Skype affected?

No. The Skype software downloaded from is not affected by the behavior. The only time "normal" Skype users are affected is when they communicate with TOM-Skype users.

What is TOM-Skype and what is the difference between it and Skype?

If you go to from China, you are redirected to — so that's version most Chinese people will use.

In 2004 Skype developed a relationship with TOM Online, a leading wireless provider in China, and announced a joint venture in 2005. Skype and TOM Online produced a special version of the Skype software, known as TOM-Skype, for use in China.

What is Skype saying, have they said anything to you?

I contacted Skype to have the security issue fixed before the report was released. So, they have configured the servers so that one can no longer view the logs and they have deleted sensitive files, such as the one containing the encryption key. Other than that contact, I've only seen the
statements they've made to reporters.

The NYT:

Jennifer Caukin, an eBay spokeswoman, said, "The security and privacy of our users is very important to Skype." But the company spoke to the accessibility of the messages, not their monitoring. "The security breach does not affect Skype's core technology or functionality," she said. "It exists within an administrative layer on Tom Online servers. We have expressed our concern to Tom Online about the security issue and they have informed us that a fix to the problem will be completed within 24 hours." EBay had no comment on the monitoring.

To the WSJ

Jennifer Caukin, a spokeswoman for Skype, said in an emailed statement that the security problem had been remedied as a result of the new report. The idea that China's government "might be monitoring communications in and out of the country shouldn't surprise anyone," Ms. Caukin said. "Nevertheless, we were very concerned to hear about the apparent security issue" that enabled people to view user information, and "we are pleased that, once we informed TOM about it, that they were able to fix the flaw."

In a separate statement, TOM Group said that "as a Chinese company, we adhere to rules and regulations in China where we operate our businesses."

The WSJ blog, has the statement in full.

In the past Skype stated:

The text filter operates on the chat message content before it is encrypted for transmission, or after it has been decrypted on the receiver side. If the message is found unsuitable for displaying, it is simply discarded and not displayed or transmitted anywhere.

What I found directly contradicts this.

How does this relate to Corporate Social Responsibility (and the voluntary Principles of Free Expression and Privacy process)?

This case demonstrates the critical importance of the issues of transparency and accountability by providers of communications technologies. It highlights the risks of storing personally identifying and sensitive private information in jurisdictions where human rights and privacy are under threat. It also illustrates the need to assess the security, privacy and human rights impact of such a decision.

Some companies, such as Google, has stated that while the censor some search results they "will not maintain on Chinese soil any services, like email, that involve personal or confidential data."

In this case Skype appears to have delegated all of the censorship and surveillance responsibilities to TOM - I don't think they read Rebecca's paper; they should. While examining the Yahoo! China - Shi Tao case she warned:

Companies that choose to ignore the broader human rights implications of their business practices are gambling with their long-term global reputations as trustworthy conduits or repositories of people's personal communications and information.

Are the "key words" censored? Or are the messages just logged?

The only key word that I could use to trigger the content filter (the messages is not displayed to the user) and have logged in the content filter logs (uploaded to the tom-skype server) was "fuck" (and variations like f*ck). If a message contains the word "fuck" it is not displayed to the user (the entire message is not displayed) and the entire message is uploaded and logged.

In the same content filter logs I found that the majority of the logged messages did not contain obscenities, like fuck. However, many of the messages contained words like "Communist Party", I counted the number of logged messages that contained these words, from that I identified what I think are key words. It is unclear if these messages are just logged, or are censored and logged.

Post questions in the comments and I'll try to answer them :)