zlacker

Do you also send "the drop isn't ready" on other days? If not the fact that you sent a message tells the attacker everything without knowing the content.

Also can anything be inferred by the length of the signal message? Do they pad they out or will all of the sudden sending a 2kb vs 3kb message give you away that something is different?

Personally if my life is on the line, I'd stick with the shoelaces.

>>willci+(OP)
Especially handy if you don't know the number of the person you need to contact or know their device has been compromised. No need to rely on technology when a simple trick will do the... erm, trick.

>>willci+(OP)
Instead of using Signal you can just upload a specific meme to /r/wallstreetbets

>>airstr+K3
Didn't the 9/11 hijackers communicate by uploading images of basketball players to sports discussion boards?

>>progre+a6
Source if you have it please.

>>armini+4d
Suggestions of coded messages/steganography were made, but I'm struggling to find anything concrete:

> Suspected ringleader Mohamed Atta was seen repeatedly by witnesses using his Hotmail account at public libraries in Florida to surf the Internet, downloading what appeared to be pictures of children and scenes of the Middle East.[1]

> Many of the hijackers were frequent visitors to libraries and internet cafes in Florida, where they are believed to have received their final orders in coded message.[2]

Pre-9/11:

> Through weeks of interviews with U.S. law-enforcement officials and experts, USA TODAY has learned new details of how extremists hide maps and photographs of terrorist targets — and post instructions for terrorist activities — on sports chat rooms, pornographic bulletin boards and other popular Web sites.[3]

[1] https://web.archive.org/web/20011005232014/https://abcnews.g...

[2] https://www.theregister.com/2001/10/11/iomart_cashes_in_on_w... ([1] and [2] found via https://www.giac.org/paper/gsec/3494/steganography-age-terro...)

[3] https://web.archive.org/web/20030606200613/http://www.usatod... (found via https://core.ac.uk/download/pdf/11308369.pdf)

>>stordo+li
I wouldn't doubt they used stenography too, was just curious if you had a source. Thanks for the effort.

>>willci+(OP)
I assume that 99% of the point of techniques like in the article is to make the communications graph unobservable. If two people have regular communication over Signal, and one is suspected to be a mole or spy, then the other one is suspicious too. But shoelace patterns in a busy city aren't traceable like that.

>>armini+tk
Nitpick intended to be helpful, "steganography" is hiding data within other data, "stenography" basically just means writing something down. Confusingly similar terms.