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---
title: Introduction
---
# Part 8 - Update (**OTA**)
## Abstract
Updating applications and firmware is essential for the development of new
features and even more to fix security bugs. However, if a malicious third party
manages to alter the content during transport, it could alter the functioning of
the system and/or applications. The security of the updates is therefore a
critical point to evaluate in order to guarantee the integrity, the
confidentiality and the legitimacy of the transmitted data.
## Attack Vectors
Updates Over The Air are one of the most common points where an attacker will
penetrate. An OTA update mechanism is one of the highest threats in the system.
If an attacker is able to install his own application or firmware on the system,
he can get the same level of access that the original application or firmware
had. From that point, the intruder can get unfettered access to the rest of the
system, which might include making modifications, downloading other pieces of
software, and stealing assets.
### Man In The Middle (MITM)
The man-in-the-middle attack is the most classic example of an attack, where an
adversary inserts himself between two communicating entities and grabs whatever
is being communicated. In the case of OTA attacks, the connection in the network
may be intercepted:
* On the internet, before the cloud back-end.
* At the base station, 3G,4G,5G connection to the internet.
* At the receiving antenna, connection to the car.
* Between the receiving antenna and the gateway router (if present), connection
within the car.
* Between the gateway router and the target component (IVI, In-Vehicle
Infotainment unit).
There are many ways to mount a MITM attack. For example, proxy tools like Burp
Proxy can be used to intercept web traffic as a man-in-the-middle. Under the
guise of being a testing tool, the proxy server is often used in attack
scenarios. It runs on a variety of platforms.
As another example, false base station attacks are known to be fairly easy to
set-up. The problem is apparently fairly prevalent in countries like China and
in the UK. These fake base stations are sometimes just eavesdropping on the
communication, but others have the potential to do serious harm.
Defenses against MITM attacks include encrypted and signed data pipes.
Furthermore, architects and developers are also recommended to encrypt and sign
the payloads that are being passed over these pipes, to defend against perusal
of the data.
### Man At The End (MATE)
The man-at-the-end attack is when an intruder analyzes the end-point of the
communication when software is accessing the data communication. This is a more
severe attack type where the attacker can:
* Steal keys.
* For example, a simple debugging session in running software could reveal a
key used in memory.
* Tamper software.
* For example, replacing just one function call in software with a NOP (i.e.
no operation) can drastically change the behavior of the program.
* Jam branches of control.
* For example, making a program take one branch of control rather than the
intended branch can mean the difference between an authorized and a
non-authorized installation.
* Modify important data.
* For example, if the data changed is a key or data leading to a control path,
then this attack can be severe.
* In the case of OTA updates, MATE attacks are particularly problematic for
the system. One of the consequences of MATE attacks can be installed
software that allows installation of any other software. For example, an
attacker might install remote access software to control any part of the
system.
--------------------------------------------------------------------------------
## Acronyms and Abbreviations
The following table lists the terms utilized within this part of the document.
Acronyms or Abbreviations | Description
------------------------- | -------------------------------------------------------------------------
_FOTA_ | **F**irmware **O**ver **T**he **A**ir
_MATE_ | **M**an **A**t **T**he **E**nd
_MITM_ | **M**an **I**n **T**he **M**iddle
_OTA_ | **O**ver **T**he **A**ir
_SOTA_ | **S**oftware **O**ver **T**he **A**ir
_TUF_ | **T**he **U**pdate **F**ramework
|
