Time Zone of Guccifer 2 cf.7z

In a recent post, I observed that the majority of the emails in the Wikileaks DNC archive were sent AFTER Crowdstrike installed their anti-Russian software on May 6.  In today’s post, I’ll look at a metadata issue concerning Guccifer 2, who was, with “high confidence”, attributed by the US intel community to be Russian, supposedly working under the personal direction of Putin.  I’m going to look closely at document metadata in the two 7z dossiers published by Guccifer 2 in fall 2016. Neither of the two dossiers contained any documents of any relevance to the 2016 election.
Earlier this year, Forensicator observed  that the ngpvan.7z dossier showed evidence of several copying and collating operations, including a copying operation in which the modification date-times of all documents were set to a 14 minute window on July 5, 2016. From analysis of the metadata, Forensicator plausibly argued that the copy-to computer was set to Eastern time zone. Forensicator didn’t comment on the other Guccifer 2 dossier (cf.7z).
I’ve closely examined both dossiers and noticed that the time zone of the cf.7z copy-to computer appears to be one hour earlier than the time zone of the copy-to computer analysed by Forensicator i.e. Atlantic Canada time.  I am much less knowledgeable than Forensicator and similar analysts in such details and am unable to present a solution.

Forensicator’s Analysis of ngpvan.7z Time Zones

The top directory of Guccifer 2’s ngpvan.7z dossier contained 13 .rar folders, 4 .zip folders and 5 documents (pdf,png).  All .rar folders had modification dates of Sept 1, 2016 – a few days before announcement of the dossier on Sept 4, 2016 (^).  All .zip files, documents in the top directory and documents in the .rar folders had modification dates of July 5, 2016.  Forensicator, working in Pacific time zone, noticed that there was a 3 hour time difference between modification times displayed for documents within the .rar files and located in the top directory (as shown in the figure below). Forensicator explained (here) this difference as due to the following: 7z stored documents in UTC while the .rar files, constructed using WinRAR4 were in local relative time, from which he deduced that the copy-to computer of the July 5 copy operation was in Eastern time zone.
His explanation is terse. To fully understand his point in operational terms, I adjusted my computer to UTC and took equivalent observations. A file outside the RAR folders (e.g. sf3.pdf), which was displayed as 15:46 Pacific, is displayed as 22:46 UTC, reflecting the 7 hour time difference. However, a files within the RAR folders (e.g. DonorsByMM.xlsx), which was displayed as 18:51 Pacific, is now displayed as 18:51 UTC.  In other words, 7z doesn’t know the correct timezone of the RAR documents and incorrectly assumes they come from the timezone of the current user.  The timezones only match using Eastern Daylight -0400.

Forensicator’s point is unequivocally correct.  I would prefer that he not have said “we need to adjust the .7z file times to reflect Eastern Time”.  Having spent time trying to parse through this, I would have said that “we need to adjust the RAR file times”, since it is the RAR timezone that 7z gets wrong, but that doesn’t impact the correctness, importance or originality of his observations.
 

July 5, 2016 Copying in cf.7z

Guccifer 2’s other 7z dossier (cf.7z) was released on October 4, 2016 in a blogpost promising (but not delivering) salacious details of the Clinton Foundation.  Like the previous dossier, the documents in cf.7z are mundane administration details of the Democratic Party of Virginia (DPVA) – not even the DNC. Whereas the documents of ngpvan.7z were all extremely stale (most recent documents from 2011), cf.7z consists of documents from 2013-2016. Its most recent document is from June 1-2, 2016, but documents originating after April 2016 are very sparse.
Three directories contain documents with modification dates of July 5, 2016.  From the time gaps in the ngpvan.7z dossier, Forensicator had postulated that a much larger copying operation had taken place on July 5.  The cf.7z documents with modification dates of July 5 seem to originate from this larger copy operation – but display as exactly one hour earlier, indicating a difference in time zone display rather than a different origin. The earliest time in the ngpvan.7z dossier was 18:39; the documents in the cf.7z/OFA directory (152.6 MB) have modification times between 17:34 and 17:38, immediately preceding allowing for the postulated one hour time zone difference:

The cf.7z/Donor Research and Prospecting contains documents with modification dates ranging from March 2015 to July 5, 2016 (plus one 2011 outlier). Some documents were copied in what Forensicator called the “Windows” style, while others, including the most recent batches (dated May 23, June 6 and July 5),  were copied in what Forensicator called the “Unix” style that was used in the July 5 copy step of ngpvan.7z.  The July 5 tranche has modification times between 17:39 and 17:52, which again fit, allowing for the proposed one hour time zone difference. (Displayed time for computer set to Atlantic Canada time match perfectly.)

Documents in a third directory (the very small cf.7z/emails directory) also match, allowing for the proposed one-hour time zone difference.

DonorsByMM.xlsx

It turns out that two documents in the cf.7z/Donor Research and Prospecting directory (DonorsBy MM.xls and DonorsByMM_2.xls) were also uploaded to the ngpvan.7z/DonorAnalysis directory where the postulated one hour time zone difference can be demonstated to one second accuracy. More detailed properties can be obtained by right-clicking on the files, with results for each shown below. To the nearest second, the respective copy times are shown as 17:52:00 and 18:51:59, one hour apart to the second.
There are differences in technique in the preparation of the two dossiers. Times in the cf.7z dossier appear to be rounded to the nearest minute or second, while times in the ngpvan.7z are chopped off. Thus a file with a time of ending in 59.6 seconds would be rounded in one case, chopped in the other. One archive used a LZMA2:26 method, while the other used m3:22. The ngpvan.7z archive mentions Win32, not mentioned for cf.7z.
Conclusion and Question
It seems certain to me that the DonorsByMM_2.xlsx document in each archive originated in a single copy operation with metadata differences arising from later processing. The timezone of the cf.7z dossier has somehow been set one hour earlier than the time zone of the ngpvan.7z dossier, which Forensicator deduced as Eastern North America. This implies Central time zone. In addition, somewhat different techniques were used in the preparation of the two dossiers. I don’t know enough of the details of the copy operations to diagnose further and would welcome any ideas.
 
[Update Sep 19- removed an incorrect speculation on upload to mediafire, which reflected my location not anyone else’s]

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