Tidbits from the New York Times:
The final phase of Mr. Hame’s training took place at an Internet cafe in Raqqa, where an Islamic State computer specialist handed him a USB key. It contained CCleaner, a program used to erase a user’s online history on a given computer, as well as TrueCrypt, an encryption program that was widely available at the time and that experts say has not yet been cracked.
More than a year and a half earlier, the would-be Cannes bomber, Ibrahim Boudina, had tried to erase the previous three days of his search history, according to details in his court record, but the police were still able to recover it. They found that Mr. Boudina had been researching how to connect to the Internet via a secure tunnel and how to change his I.P. address.
Though he may have been aware of the risk of discovery, perhaps he was not worried enough.
Mr. Boudina had been sloppy enough to keep using his Facebook account, and his voluminous chat history allowed French officials to determine his allegiance to the Islamic State. Wiretaps of his friends and relatives, later detailed in French court records obtained by The Times and confirmed by security officials, further outlined his plot, which officials believe was going to target the annual carnival on the French Riviera.
Mr. Hame, in contrast, was given strict instructions on how to communicate. After he used TrueCrypt, he was to upload the encrypted message folder onto a Turkish commercial data storage site, from where it would be downloaded by his handler in Syria. He was told not to send it by email, most likely to avoid generating the metadata that records details like the point of origin and destination, even if the content of the missive is illegible. Mr. Hame described the website as “basically a dead inbox.”
The ISIS technician told Mr. Hame one more thing: As soon as he made it back to Europe, he needed to buy a second USB key, and transfer the encryption program to it. USB keys are encoded with serial numbers, so the process was not unlike a robber switching getaway cars.
“He told me to copy what was on the key and then throw it away,” Mr. Hame explained. “That’s what I did when I reached Prague.”
Mr. Abaaoud was also fixated on cellphone security. He jotted down the number of a Turkish phone that he said would be left in a building in Syria, but close enough to the border to catch the Turkish cell network, according to Mr. Hame’s account. Mr. Abaaoud apparently figured investigators would be more likely to track calls from Europe to Syrian phone numbers, and might overlook calls to a Turkish one.
Next to the number, Mr. Abaaoud scribbled “Dad.”
This seems like exactly the sort of opsec I would set up for an insurgent group.
EDITED TO ADD: Mistakes in the article. For example:
And now I’ve read one of the original French documents and confirmed my suspicion that the NYTimes article got details wrong.
The original French uses the word “boîte”, which matches the TrueCrypt term “container”. The original French didn’t use the words “fichier” (file), “dossier” (folder), or “répertoire” (directory). This makes so much more sense, and gives us more confidence we know what they were doing.
The original French uses the term “site de partage”, meaning a “sharing site”, which makes more sense than a “storage” site.
The document I saw says the slip of paper had login details for the file sharing site, not a TrueCrypt password. Thus, when the NYTimes article says “TrueCrypt login credentials”, we should correct it to “file sharing site login credentials”, not “TrueCrypt passphrase”.
MOST importantly, according the subject, the login details didn’t even work. It appears he never actually used this method — he was just taught how to use it. He no longer remembers the site’s name, other than it might have the word “share” in its name. We see this a lot: ISIS talks a lot about encryption, but the evidence of them actually using it is scant.