N°1: Attackers will always find their way
Whatever system, an
attacker will find one day a weakness. Thus, during design,
renewability of security is a mandatory feature. An example
of
renewability is the use of removable secure modules such as smart
cards. This explains how pay TV survived numerous attacks for
two
decades.
N°2: Know the assets to protect
It is important to know the
assets to protect., the potential attackers and the threats.
Before starting any design, it is mandatory to perform a threat
analysis. The threat analysis identifies the most probable
threat and the associated potential losses. Unfortunately, there is
no established methodology;
N°3: No security by obscurity
In XIX
th century,
KERCKHOFFS Auguste issued his famous law: The security of a
system should rely on the secrecy of its keys and not of its
algorithms. Many examples proof the truth of this law.
The
secret keys are probably the most important asset to protect.
Recent attacks on AACS once more
highlighted it.
N°4: Trust no one
A key element is the trust model. It lists all the hypotheses on which
security rely. These hypotheses are the foundations of the system.
The more there are hypotheses, the higher the probability that one of them will
fail. Thus, trust no one.
N°5: Si vis pacem, para bellum*
Due to law 1, there will always be successful attacks. Thus, it is
important to design countermeasures before occurrence of the attacks.
Two possible strategies: waiting until the attacks occurs to deploy the
countermeasure, or update continuously update the target to weaken the
attack. The choice depends on many factors such as cost, losses and acceptable
risks.
It is mandatory to know our opponents. Thus it is mandatory to survey the
scene and the darknet to learn about the latest exploits and the newest hacking
tools..
"* Who wants peace, prepares war"
N°6: You are the weakest link
People are often the weakest link of any secure system. The simplest
illustration is the management of passwords. Useless to remind stories of
weak or lost passwords, or post it near the computer's screen. Unfortunately,
social engineering is a underestimated threat. Social engineering
gains unauthorized access or secret information through human interaction,
often through impersonation.
The best countermeasure is to design the security to be as transparent as
possible for the users. Training the users is another countermeasure.
N°7: Security is not stronger than its weakest link
Indeed a trained hacker will look for this weakest point to attack. It is
paramount to know the robustness of each parts of a secure system. If
investment is possible, put it on this point.
For instance, it is useless to put a vault door to a house if the
windows are not protected and easily reachable.
N°8: If you are connected to the Internet, then the Internet
is connected to you
A door in a fence is also a potential opening for an attacker. Thus, it is
important to follow some rules:
- Never let a door open when unused
- Monitor any opened door
Internet offers many opportunities but also a wealth of potential threats.
N°9: Quid custodient ipsos custodies ?*
This rule has two aspects. It is mandatory to have security
policies that define mutual controls. It is also important to
assess the right implementation of these policies.
Good practices in security require to log all events in files. These files
are useless if not used. The analysis may happened once an incident was detected.
But it would better to analyze the logs to detect suspicious events.
"*Who guards the guardians?"
N°10: Security is not a product but a process
Security is a mindset and is in continuous motion. Security is an endless
race with attackers. It requires continuous monitoring of the attackers,
of the newest exploits, and assessment of the efficiency of the deployed
solutions.