Nama Kelompok : 1.Arini Sukmawati ( ) 2.Arif Rahman F. ( ) 3.Muhammad Reggi H. ( ) IK-33-01

PASSWORD ATTACK

Password cracking is the process of recovering passwords from data that has been stored in or transmitted by a computer system

●Serangan Sandi ditandai oleh serangkaian login gagal dalam waktu singkat oleh seorang penyerang. ●Pengguna akan mendapatkan catatan di layar tentang berapa banyak usaha yang gagal di account Anda. ●Dalam hal ini terjadi, Anda harus segera mengubah sandi Anda.

Passwords to access computer systems are usually stored in a database so the system can perform password verification when a user attempts to login or access a restricted resource. To preserve confidentiality of system passwords, the password verification data is typically not stored in cleartext form, but instead a one-way function is applied to the password, possibly in combination with other data, and the resulting value is stored.

When a user later attempts to authenticate by entering the password, the same function is applied to the entered value and the result is compared with the stored value. If they match, there is an extremely high likelihood the entered password was correct. For simplicity in this discussion, we will refer to the one way function employed (which may be either an encryption function or cryptographic hash) as a hash and its output as a hashed password.

If a system uses a poorly designed password hashing scheme to protect stored passwords, an attacker can exploit any weaknesses to recover even 'well-chosen' passwords. One example is the LM hash that Microsoft Windows XP and previous uses by default to store user passwords of less than 15 characters in length. LM hash converts the password into all uppercase letters then breaks the password into two 7-character fields which are hashed separately—which allows each half to be attacked individually.

Passwords can sometimes be guessed by humans with knowledge of the user's personal information. Examples of guessable passwords include: blank (none) the words "password", "passcode", "admin" and their derivatives a row of letters from the qwerty keyboard -- qwerty itself, asdf, or qwertyuiop) the user's name or login name the name of their significant other, a friend, relative or pet their birthplace or date of birth, or a friend's, or a relative's their automobile license plate number, or a friend's, or a relative's their office number, residence number or most commonly, their mobile number. a name of a celebrity they like a simple modification of one of the preceding, such as suffixing a digit, particularly 1, or reversing the order of the letters. a swear word. and so, extensively, on.

Early Unix implementations limited passwords to 8 characters and used a 12-bit salt, which allowed for 4096 possible salt values. While 12 bits was good enough for most purposes in the 1970s (although some expressed doubts even then), by 2005 disk storage had become cheap enough that an attacker can precompute the hashes of millions of common passwords, including all 4096 possible salt variations for each password, and store the precomputed values on a single portable hard drive.

Serangan Yang Sering Dipakai Hacker 1)DDoS (Distributed Denial Of Service) [classic] Distributed Denial Of Service digunakan seorang hacker untuk mengambil resource didalam network tanpa adanya autorisasi. Sebelumnya hacker harus melakukan FTP Attack. 2)IP Spoofing (Atau Source Address Spoofing) pemalsuan alamat IP hacker sehingga sasaran menganggap alamat IP hacker adalah alamat IP dari host di dalam network bukan dari luar network. Misalkan hacker mempunyai IP address type A xx.xx ketika hacker melakukan serangan jenis ini maka Network yang diserang akan menganggap IP hacker adalah bagian dari Networknya. IP Spoofing terjadi ketika seorang hacker menghack packet routing untuk mengubah arah dari data atau transmisi ke tujuan yang berbeda. Packet untuk routing biasanya di transmisikan secara transparan dan jelas sehingga membuat hacker dengan mudah untuk memodifikasi asal data ataupun tujuan dari data.

3) FTP Attack (File Transfer Protocol Attack) serangan buffer overflow yang diakibatkan oleh malformed command. tujuan menyerang FTP server ini rata-rata adalah untuk mendapatkan command shell ataupun untuk melakukan DDoS. 4) UFE (Unix Finger Exploits) Serangan ini terjadi karena kesalahan sistem Administrator yang tidak menggunakan keamanan sedikit atau sama sekali tidak. Point ini terlalu berharga untuk dilewatkan.

5) Flooding & Broadcasting (Pembanjiran server) Serangan ini digunakan dengan tools-tools untuk pembanjiran server. Misalkan TrashAttack. Tujuan serangan ini adalah untuk memperlambat kinerja server. 6) FPA (Fragmented Packet Attacks) Data-data internet yang di transmisikan melalui TCP/IP bisa dibagi lagi ke dalam paket-paket yang hanya mengandung paket pertama yang isinya berupa informasi bagian utama dari TCP/IP. Beberapa firewall akan mengizinkan untuk memroses bagian dari paket-paket yang tidak mengandung informasi alamat asal pada paket pertamanya, hal ini akan mengakibatkan beberapa type system menjadi crash.

7) Exploits Terbagi menjadi lima cara yaitu: mail floods,command manipulation, transport level attack, malicious code inserting dan social engineering.