Common problems about mainland China Internet police. (Continually updated)

This is a translation. The original article: 中国大陆网安常见问题 Q&A
(MAY CONTAINS MISTAKES)


Dear fellows of Pincong, this is 十二月的冬天. As a newcomer, I'm very happy to be part of the forum.

I used to work in the Chinese Police Department, started with working as a Internet police. Because of good people skills, there was also a brief exposure to other types of police work. But in the end, it revolves around the Internet police. Until this recent period, I quit my job because of the pressure from the superior.  I've seen many people in Pincong ask questions about Internet censorship and Internet police in mainland China and about my former profession, but for a variety of reasons they didn't get reliable answers. I hope to help you all by answering questions in the capacity of a Internet police.

With a wide range of relationships and the way of escaping in the real world, there's no need to worry about my safety.

The following questions are from fellows of Pincong:

Q: Are all mainland Chinese chat apps (including self-proclaimed safe) censored?
A: Censorship exists for all products operated by companies in mainland China. The categories of censorship are keyword censorship, image censorship, document censorship (e.g. video files sent, etc.), and voice keyword censorship.

Q: Can you elaborate how these types of reviews work?
A:

[li]Keyword censorship: in private chats, if sensitive words appear in the content of the chat, the content in that private chat will be sent to the police for manual review in a period of time. (According to what I learned in 2018, content with sensitive words on WeChat is sent within 72 hours, for QQ is within 24 hours, for Yixin is within 48 hours, and other platforms are within a few dozen hours to a week.) If it's a group chat, it works similarly to the above, but the difference is the censorship is more stringent, and sometimes the other side can't view the sensitive words you sent.[/li][li]Image censorship: Optical character recognition (OCR) and MD5 comparison are used to prevent some images from being sent and passed on. Once a suspicious image is identified, both cases of sending out or not will be recorded and reported to the relevant police departments. (The step of judging the picture is still with the major service providers, and will only be synchronized to the police related departments when the picture is judged to be suspicious)[/li][li]File censorship: Using MD5 comparison or the timing of the cloud server to obtain the source information of the file to determine whether the file is suspicious. if it is suspicious it will be actively banned by the chat software, and it will appear that it cannot be sent out or the other side can't download.[/li][li]Voice keyword review: This is currently only available from Tencent, with the aim of collecting voice pattern information for AI training and a new way of keyword censorship.[/li]

Q: Are the files uploaded to mainland China's cloud storage under police surveillance?
A: The police cannot directly see the content uploaded to the user's cloud storage. But for the control of the dissemination of suspicious or prohibited by law in mainland China, the service provider has already conducted a censorship during the upload stage (when the user uploads a file, it determine whether the file is suspicious or prohibited by law through the file name, MD5, thumbnail, etc. ). If it's a known file, it'll be directly prohibited; if it's not, it will be copied to a dedicated server and stored by the service provider for self-examination by first. But of course, the police with permission can directly access the suspicious files placed here, and the file itself and some source information are clear.

Q: What exactly is the level of surveillance in the real world in mainland China?
A: There is no privacy once you leave the house.

Q: How did the police find the person posting sensitive post on the offshore platform?
A: Most of them are found through social engineering (Through the general social engineering approach with the advantages of police authority to find people, Internet police and criminal police department own special people to do this). The next is the type of self-reporting and public privacy. (In fact, the last kind is the most trouble-free－not waiting for the police investigation, things they need already in the hacker's public data.)

Q: How did the police crack the password of the "criminal's" phone?
A: There are several ways of doing it.

[li]Phones produced in mainland China (mainland China Brands): It's straightforward for the manufacturer to unlock with no effort.[/li][li]Overseas brand mobile phones (mainland Chinese edition): Through the back door to unlock, put pressure on manufacturers if it's not working. (Before other police friends told me that this trick is really good because no manufacturer will not be with the money. It has proved effective every time)[/li][li]Iphone: Bypassing the retry protection mechanism of the lock screen password through system vulnerabilities.(As I know, the longest record of cracking IphonEX with 6-digit password is 108 hours, for Iphone7 Plus (and previous models) with 4-digit is 12 minutes.)[/li][li]Overseas brand phones: Hacking through known Android vulnerabilities, or the hardware chip shorting method.[/li][li]Unbreakable phones: If it is a criminal case, the suspect is forced to reveal the password by abusing. If it is a social case, the suspect will be forced to reveal the password through psychological techniques that cause significant emotional changes. In the case of particularly difficult cases, the suspect will be forced to reveal the password by means of electric shocks with police weapons or by brutalizing his family. (including but not limited to cutting off water and food to the suspect, threatening his family and friends, etc.)[/li]

Q: Is this kind of work well paid? Is doing this against your conscience?
A:

[li]Income: In terms of my income from my job at the time, it was just enough to feed two people.[/li][li]Mental state: It is indeed against the conscience. And because of the need of lying, some retired from this profession lie into unmanageable, even caused their own lives serious impact. I finally left because of the pressure problem.[/li]

Q: Is Pinnacle being specifically targeted? Is there a specifically targeted platform?
A: Zhinawiki, Pincong, Caoliu, are being paid special attention.

Q: Is it safe to install original Android on mainland China's phones? (Can this way block the general cracking of the password and the risks of network security?)
A: For resisting the crack of the password will actually be more insecure. Because before installing you need to unlock bootloader, and that equals the door opened to anyone. At this time cracking the password is super simple, just install a specific recovery to replace the relevant files in the system, or use the fastboot instructions to erase a partition and then re-write it. If unlocked and installed but without rooted, from the point of view of general network security, that will indeed be better than using the domestic system. But the advantages are not obvious.

These are follow-up additions, from questions from fellows of Pincong recently:

Q: Why and what do you say these out for?
A: First of all, I have a bad conscience. The second is because of factional infighting within the system (sort of).

Q: Why did you pick Pincong to say this? Is there any ulterior purpose?
A: It's just because Pincong is safe. (There is a rumor in the group that the police, who were investigating the zhinawiki case that leaked the identity of Xi Mingze and others, had used some facilities in Guangdong and Shenyang to launch a cyber attack on Pincong in order to collect evidence. But in the end, it lasted for more than two months but nothing was found, so they had to give up, around March 2020.)

Q: Is there surveillance of ordinary phone calls and text messages in mainland China?
A: For in-country contact, unless it is a key person or a key region, only keyword filtering exists for SMS (SMS containing sensitive words will not be sent out or will even lead the SIM to deactivated), and there is no surveillance for phone calls.
For foreign contacts or domestic contacts, phone calls are always recorded and SMS messages are subject to more keyword filtering and region-specific interception (e.g. mainland China generally intercepts messages sent to Taiwan and Iran).

Q: Will Mainland China's phones cooperate with software vendors to open backdoors?
A: For now, Xuexiqiangguo and Meitu are on the whitelist of mainland China's manufacturers (Xiaomi, Huawei, OPPO, VIVO), and any data collection by these two apps will not be overlooked by the system's security software. Of course, this is limited to the collection of information. As for backdoors like this I'm not sure what will happen in the future.

Q: How many years have you been in this business? Don't you feel guilty about what you've done (til leaving)?
A: As of the separation, there have been more than ten years, this line of work belongs to the relatively strong confidentiality of the profession, which only the practitioners know the warm and cold.
Of course, I feel shame. So I am still in the job is very conservative, trying to do least if possible.

Q: What are the safest measures to visit sensitive websites?
A: If it is on a computer, then the well-known protection measures should be applied. If it is on a cell phone, especially a mainland China's phone, then of course the same protection measures are needed. But if it's not a mainland China's phone, multi-hopping proxies, chrome private mode, isolated identity, that's enough.

05/02/2021 added.

Q: For the average person, should I protect myself with measures equivalent to programthink?
A: You don't really need to become that way, but it's worth learning some of the good ways to protect your privacy that this person recommends. In addition, this pal's drawing of the "zhao" is also very close to the real situation, and is worth reading.

Q: What should I do to avoid the common surveillance of some chat software? Is it really impossible to avoid?
A: For the focus on the people, of course, can not be avoided, but for the general population, there are still many ways to do that.
[li]Do not send text of sensitive topics , use the phone call or voice messages to send, it's better to use Chinese dialect as much as possible.[/li][li]When sending sensitive pictures and sensitive files, send a zip file encrypted by a password and change the file name to an insignificant name or a name that only two people know the meaning of, the more obscure the better.[/li][li]If you have to send text to discuss sensitive topics, then you can randomly disrupt the order without affecting the reading, and for sensitive words, you can use misspelled words instead.[/li]

05/03/2021 added.

Q: (Asked by Pincong fellow) There is a video on the Internet, which is said to be the screen of the Internet police when monitoring the speech. In the video you can see a house with a set of shelves full of cell phones, there is still WeChat change the interface from time to time. Is this true?
A: No, this is not true. None of the various divisions of the Internet police work in this manner. The only information system used by the Internet police on a regular basis is opened through a browser.
This is actually a picture of some commercial marketing companies or individual micro-businesses doing marketing activities or group messaging, and the equipment (or system) used in the video is called group control.

Q: Are there any differences of the censorship between chat software and platforms like postbar? Can you elaborate on this?
A: The only difference is that for posting platforms, there is an additional self-censorship on posting platforms before sending posts to the police. This step goes to the police when the published speech is likely to cause real harm, otherwise the platform removes itself.
(Censorship on chat software: User → Sensitive speech → Police
  Public platforms (e.g. posting forums): users → Sensitive speech → Platforms' self-censorship → police)

05/05/2021 added.

Q: (Asked by Pincong fellow) Is there any sexual harassment, abuse of prisoners, etc. in the prison system in mainland China? Is Xinjiang what it is rumored to be?
A: [b]Abuse exists in prisons, and I have seen it with my own eyes (in the south of China, prison guards are frank with people who are part of the public security system). They mainly happen on prisoners with insubordination. The situation is even more heavy to the political prisoners who are held in deeper areas (petitioners, demolitioners, and human rights lawyers). The sexual harassment, according to my experience, if there is, it is an isolated case. It is not a common phenomenon.
[/b]
I have not been in contact with the prison system in Xinjiang, so I'm not sure what the situation is. What I can tell you for sure about the other rumors is that forced labor does exist in Xinjiang, but it's not race-specific, it's population-specific.



Q: What information does the service provider get when connecting to a public WiFi?

A:

[li]The MAC address of the phone. (If this is provided to the app service provider then they can determine who the user is.)[/li][li]The phone number and the identity information of the user.[/li][li]The brand, model and year of manufacture of the phone.[/li][li]If the connection time is long enough, then the user's network product usage preferences can be derived.[/li]


This is all I have gathered for now, so please remember to comment if you have something else to ask. I will try my best to reply to all of you about the real situation without exposing myself, thank you. (Please excuse the slow response)