Google Chrome distribution knows who downloaded it

Updating my software collection, I found that Google issues different versions of the Chrome browser for downloading (offline installer, ChromeStandaloneSetup.exe file), depending on which computer you download it from, which account, which browser and other parameters. Perhaps this data subsequently affects the operation of this program on this computer, and perhaps not. Anyway, this creates an inconvenience, since the checksums for different “options” of the distribution will be different and there is nothing to reconcile with.

Download the latest version of Chrome offline installer for Windows OS, from the Stable branch at a permanent link: ChromeStandaloneSetup {64} .exe . There is also a Google Chrome download site for Windows where you can find current installers for all platforms. I downloaded the 64-bit Russian browser distribution from these two sources and compared them.

It turned out that distribution files (ChromeStandaloneSetup64.exe) have one size (50 688 616 bytes), are digitally signed with one date (September 21, 2017 10:32:14), have one version on the “Details "File properties (1.3.33.5), but with binary comparison differ. Several blocks are different at the end, where you can read some metadata in binary browsing: (N) app , guid = .., iid = .., lang = .., browser = .., usagestats = .., appname = .. , needsadmin = .., ap = .... I compared the built-in Total Commander tool:


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Format and estimated values ​​of metadata fields:
(indicates whether the value of the two files matches or not)

• (N) app - the difference in the byte before the “app” may be some kind of trigger switch;
• guid = {FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF} - the field in the 16-primary record; matches
• iid = {FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF} - the field in the hexadecimal record; does not match
• lang = ru - language; matches
• browser = d - decimal digit, perhaps the browser code that downloaded the installer. Values ​​3 and 4; does not match
• usagestats = 0 - decimal digit 0, cancels statistics collection. This is asked before loading in the License Agreement window; matches
• appname = Google% 20Chrome - the name of the application; matches
• needsadmin = s - text string. “Prefers” and “true” values; does not match
• ap = s is a text string, some different colors in the Stable branch. The endings of x64-stable and x64-stable-statsdef_1; does not match

To whom it is interesting to check everything yourself, you can download this distribution by link using different browsers on your computer, under different accounts, from different computers - files will differ in the specified metadata fields.

I think this practice: "multivariate" distributions apply to other Google products. Now I understand why checksums are not indicated anywhere for verification.