Security researchers have found a major flaw in the Automatic Identification System (AIS), a mandatory tracking system for ships, which could leave the 400,000 vessels currently using it globally wide open to terrorists or pirates.
Trend Micro’s Kyle Wilhoit and Marco Balduzzi and independent researcher Alessandro Pasta presented their findings at the HITB security conference in Kuala Lumpur this week.
They claimed that AIS has been designed “with seemingly zero security considerations”, potentially allowing hackers to create fake vessels, disable tracking or create false SOS or collision alerts.
Given that the system is mandatory for all commercial ships over 300 metric tons and all passenger ships regardless of weight, the security flaws highlighted in the research are nasty.
AIS works by grabbing GPS data on a ship’s position, course and other info and exchanging it with nearby ships and AIS base stations along the coastline.
However, in a blog post, Wilhoit and Balduzzi explained that they’d found vulnerabilities not only in the AIS protocol but also within service providers such as Marine Traffic which use AIS info on their public-facing sites.
They claimed some of the main providers have vulnerabilities which would allow a hacker to “tamper with valid AIS data and inject invalid AIS data”, leading to a variety of possible outcomes.
These include changing vital ship details such as position, course, speed, cargo or unique MMSI (Mobile Maritime Service Identity).
It could also allow the creation of fake vessels – they gave the example of an Iranian ship filled with nuclear cargo turning up off the US coast.
Hackers could force shipwrecks by “creating and modifying Aid to Navigations (AToN) entries, such as buoys and lighthouses”, and even spoof the take-off and flight of search and rescue aircraft.
Wilhoit and Balduzzi also found flaws in the AIS protocol used in hardware transceivers installed in all vessels using the system.
This could lead to the following scenarios, they claimed:
Impersonate marine authorities to permanently disable the AIS system on a vessel, both forcing the ship to stop communicating its position, and stop getting AIS notifications from all nearby vessels (essentially a denial of service attack). This can also be tagged to a geographical area e.g. as soon as ship enters Somalia sea space it vanishes of AIS, but the pirates who carried out the attack can still see it.
Fake a “man-in-the-water” distress beacon at any location that will also trigger alarms on all vessel within approximately 50 km.
Fake a CPA alert (Closest Point of Approach) and trigger a collision warning alert. In some cases this can even cause software on the vessel to recalculate a course to avoid collision, allowing an attacker to physically nudge a boat in a certain direction.
Send false weather information to a vessel, e.g. approaching storms to route around.
Cause all ships to send AIS traffic much more frequently than normal, resulting in a flooding attack on all vessels and marine authorities in range.
The problem, the duo claimed, is that AIS was “designed in a world before the Internet or software-defined radio”.
This means it lacks basic security measures such as geographical validity checks to ensure the accuracy of AIS messages; time-stamping of messages; authentication of message senders; and encryption to prevent message interception/modification.
Trend Micro said it will be releasing a white paper around the findings in due course and has already disclosed its research to all major AIS standards bodies and online AIS tracking info providers. ®