Table of Contents
- 1 Which is the most appropriate countermeasure to protect against offline rainbow table attacks?
- 2 What is an offline attack?
- 3 What is online attack and offline attack of password cracking?
- 4 How does a rainbow table help an attacker?
- 5 What is online guessing attack?
- 6 How does offline cracking work?
- 7 What does a reduction function do?
- 8 Why are rainbow table attacks superior to brute force?
- 9 What is the use of passwd and shadow file?
- 10 How to address shadow IT risks in your organization?
- 11 How do I view the contents of the /etc/shadow file?
Which is the most appropriate countermeasure to protect against offline rainbow table attacks?
Experts say the best defense against rainbow tables is to “salt” passwords, which is the practice of appending a random value to the password before it is encrypted.
What is an offline attack?
Definition(s): An attack where the Attacker obtains some data (typically by eavesdropping on an authentication protocol run or by penetrating a system and stealing security files) that he/she is able to analyze in a system of his/her own choosing.
What is offline brute force attack?
Brute-force attacks can take place offline or online. In case of an offline attack, the attacker has access to the encrypted material or a password hash and tries different key without the risk of discovery or interference. In an online attack, the attacker needs to interact with a target system.
What is online attack and offline attack of password cracking?
While online password attacks are limited by the speed of the network, offline password attacks are limited only by the speed of the computer the attacker is using to crack them. That means that an 8 character password can be brute forced (every possible combination of characters) in less than 3 days.
How does a rainbow table help an attacker?
A rainbow table attack is a password cracking method that uses a special table (a “rainbow table”) to crack the password hashes in a database. If hackers gain access to the list of password hashes, they can crack all passwords very quickly with a rainbow table.
What is it called when a random hash is used to defend against dictionary or rainbow table attacks?
Password Salting, aka Defense against above Attacks Salts protect against rainbow table and dictionary attacks wherein the hashes of many likely inputs are precomputed so that the observed hash can simply be looked up to reveal the input.
What is online guessing attack?
Definition(s): An attack in which an attacker performs repeated logon trials by guessing possible values of the authenticator output.
How does offline cracking work?
Offline Password Cracking is an attempt to recover one or more passwords from a password storage file that has been recovered from a target system. Using Online Password Cracking, an attacker does not have to have any previous access to the system.
Which of the following is not an example of offline password attack?
14. Which of the following is not an example of offline password attack? Explanation: The offline attack needs physical access to the system that is having a password file or the hacker needs to crack the system by other means. A dictionary attack, rainbow, and brute force come under offline attack.
What does a reduction function do?
The reduction function is the glue which turns a hash function output into an appropriate input (for instance a character string which looks like a genuine password, consisting only of printable characters).
Why are rainbow table attacks superior to brute force?
Rainbow table attacks form a point on the spectrum of the space-time trade-off that occurs in exhaustive attacks. However, not having each case on hand at run time leads to run time computation longer than dictionary attacks but much lesser than brute force thanks to the precomputed end points (roughly k operations).
Are rainbow tables still used?
modern password cracking. From a modern password cracking threat perspective though, rainbow tables are mostly obsolete, and that’s not only due to the previously mentioned commonality of password salting that makes them ineffective.
What is the use of passwd and shadow file?
The most commonly used and standard scheme is to perform authentication against the /etc/passwd and /etc/shadow files. /etc/shadow is a text file that contains information about the system’s users’ passwords. It is owned by user root and group shadow, and has 640 permissions .
How to address shadow IT risks in your organization?
When approaching the shadow IT problem carefully, you can not only detect cybersecurity risks but also test various technologies and choose more efficient tools for your organization. Doing so may help you optimize your expenses and find weak spots in current work processes. Now, let’s explore in detail how you can address common shadow IT risks.
What is shadowshadow it and how does it affect your business?
Shadow IT may break compliance with various regulations, standards, and laws, which in turn may lead to fines, lawsuits, and reputational losses. For instance, under the General Data Protection Regulation (GDPR), organizations are obliged to process users’ personal data lawfully, fairly, and transparently.
How do I view the contents of the /etc/shadow file?
You can view the contents of the file, with a text editor or a command such as cat : Typically, the first line describes the root user, followed by the system and normal user accounts. New entries are appended at the end of the file. Each line of the /etc/shadow file contains nine comma-separated fields: