Exploring Weak Cipher Usage in Avionic Communications via ACARS

[skeezix]

http://fc17.ifca.ai/preproceedings/paper_17.pdf

Abstract.
Recent research has shown that a number of existing wireless avionic systems lack encryption and are thus vulnerable to eavesdropping and message injection attacks. The Aircraft Communications Addressing and Reporting System (ACARS) is no exception to this rule with 99% of the tra c being sent in plaintext. However, a small portion of the tra c coming mainly from privately-owned and government aircraft is encrypted, indicating a stronger requirement for security and privacy by those users. In this paper, we take a closer look at this protected communication and analyze the cryptographic solution being used. Our results show that the cipher used for this encryption is a mono-alphabetic substitution cipher, broken with little e↵ort. We assess the impact on privacy and security to its unassuming users by characterizing months of real-world data, decrypted by breaking the cipher and recovering the keys. Our results show that the decrypted data leaks privacy sensitive information including existence, intent and status of aircraft owners.

[Fansome]

David Kahn's "The Code Breakers".

[sat_dxer]

"attacker who is passive with respect to the medium but actively decrypts messages...An attacker of this capability could achieve their aims for a relatively low
financial outlay...an attacker will be able to collect ACARS messages from aircraft...We consider a typical attacker...attacker would be able to deploy...attacker as defined in our threat model...which might be valuable to an attacker"

Written by computer swots with a public policy agenda

[Pigmeat]

David Kahn's "The Code Breakers".

You can't cipher, but you can read? How did you get out of sixth grade and into CalTech? That rich Uncle of yours probably had something to do with it.

BTW, did he ever have that "long talk" with you?