Sina UC Censorship Research

Jeffrey Knockel
Sina UC censorship warning
"消息包含敏感字符!" (Message contains sensitive characters!)

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Censorship of the Day

These are recently retrieved, decrypted lists of the keywords that Sina UC downloads when starting up.

Censorship Analysis

Sina UC has two sources for lists of keywords: built-in and downloaded. Both sources are encrypted with the 'H177UC09VI67KASI' 16-byte Blowfish key in ECB mode, then JSON-encoded, then encoded as an ASCII hex string. The built-in source is embedded in IMResource.dll. The downloaded source is retrieved from Each source contains five lists of keywords (downloaded list retrieved 8/25/11):


The first python program takes an ASCII hex string from stdin and outputs the decrypted JSON plaintext to stdout. The second program takes a JSON file foo and outputs a file fooi containing a line-delimited list of keywords for each keyword list i in foo.

This material is based upon work supported by the National Science Foundation under Grant No. 0844880. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.