Schneier on Security

El Chapo's Opsec

I’ve already written about Sean Penn’s opsec while communicating with El Chapo. Here’s the technique of mirroring, explained:

El chapo then switched to a complex system of using BBM (Blackberry’s Instant Messaging) and Proxies. The way it worked was if you needed to contact The Boss, you would send a BBM text to an intermediary (who would spend his days at a public place with Wi-Fi) this intermediary (or “mirror”) would then transcribe the text to an I-Pad and then send that over a Wi-Fi network (not cellular networks which were monitored constantly by law enforcement). This WiFi text was then sent to another cut-out who would finally transcribe the message into a Blackberry BBM text and transmit it to Guzman. Although Guzman continued to use his Blackberry, it was almost impossible to analyze the traffic because it now only communicated with one other device. This “mirror” system is difficult to crack because the intermediaries or proxies, can constantly change their location by moving to new WiFi spots.

This article claims he was caught because of a large food order:

After construction was complete, the safehouse was quiet. Until 7 January 2016, when a car arrives carrying unknown passengers. Security forces suspected that this was Guzman. There was one final indicator that someone important enough to require an entourage was inside. A white van went off, at midnight, to fetch enough tacos to feed a large group of people. The police raided the house 4 hours later.

Here’s more detail about El Chapo’s opsec at the time of his previous capture.

EDITED TO ADD (2/11): More on his opsec.

Posted on January 21, 2016 at 6:19 AM • View Comments

Sean Penn's Opsec

This article talks about the opsec used by Sean Penn surrounding his meeting with El Chapo.

Security experts say there aren’t enough public details to fully analyze Penn’s operational security (opsec). But they described the paragraph above as “incomprehensible” and “gibberish.” Let’s try to break it down:

• Penn describes using “TracPhones,” by which he likely means TracFones, which are cheap phones that take calling cards so they’re not linked to a credit card or account. They’re often called burners, but you don’t actually throw it in the trash after a call; instead you might swap out the SIM card or use different calling cards for different people. Hollywood loves these! Katie Holmes reportedly used one to plan her divorce from Tom Cruise. They’re a reasonable security measure, but it still creates phone records that live with, and can be requested from, cell phone carriers.
• Penn says he “mirror[ed] through Blackphones,” which are relatively expensive phones sold by Silent Circle that offer a more secure operating system than a typical off-the-shelf phone. It runs Internet through a VPN (to shield the user’s IP address and encrypt their Web traffic) and end-to-end encrypts calls and messages sent to other Blackphones. Unlike with the TracFone, Penn would have a credit card tied to the account on this phone. It’s unclear what Penn means when he says he “mirrored” through the phone; the phrase “mirrored” typically means to duplicate something. As he wrote it, it sounds like he duplicated messages on the secure Blackphone that were being sent some other, potentially less secure, way, which would be dumb, if true. “I’m not sure what he means.” said Silent Circle CEO Mike Janke via email. “It’s a strange term and most likely he doesn’t know what he is saying.”
• Penn says he used “anonymous” email addresses and that he and his companions accessed messages left as drafts in a shared email account. That likely means the emails were stored unencrypted, a bad security practice. If he were sharing the account with a person using an IP address that was the target of an investigation, i.e. any IP address associated with El Chapo’s crew, then all messages shared this way would be monitored. For the record, that did not work out very well for former CIA director David Petraeus, who used draft messages to communicate with his mistress and got busted when her IP address was targeted in an online harassment investigation.
• Elsewhere in the article, Penn says Guzman corresponded with Mexican actress Kate del Castillo via BBMs (Blackberry messages). Those only have unique end-to-end encryption if a user has opted for BBM Protected. Law enforcement has been able to intercept BBMs in the past. And Mexican officials have told the media that they were monitoring del Castillo for months, following a meeting she had last summer with El Chapo’s lawyers, before she had reached out to Penn. Law enforcement even reportedly got photos of Penn’s arrival at the airport in Mexico.
• In the most impressive operational, if not personal, security on display, Sean Penn says that when he traveled to Mexico, he left all of his electronics in Los Angeles, knowing that El Chapo’s crew would force him to leave them behind.

There has been lots of speculation about whether this was enough, or whether Mexican officials tracked El Chapo down because of his meeting with Penn.

Posted on January 14, 2016 at 6:32 AM • View Comments