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Dictionary attack

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157:. A dictionary attack tries only those possibilities which are deemed most likely to succeed. Dictionary attacks often succeed because many people have a tendency to choose short passwords that are ordinary words or common passwords; or variants obtained, for example, by appending a digit or punctuation character. Dictionary attacks are often successful, since many commonly used password creation techniques are covered by the available lists, combined with cracking software pattern generation. A safer approach is to randomly generate a long password (15 letters or more) or a multiword 25: 193:. Pre-computed dictionary attacks are particularly effective when a large number of passwords are to be cracked. The pre-computed dictionary needs be generated only once, and when it is completed, password hashes can be looked up almost instantly at any time to find the corresponding password. A more refined approach involves the use of 189:. This requires a considerable amount of preparation time, but this allows the actual attack to be executed faster. The storage requirements for the pre-computed tables were once a major cost, but now they are less of an issue because of the low cost of 153:); however, now there are much larger lists available on the open Internet containing hundreds of millions of passwords recovered from past data breaches. There is also cracking software that can use such lists and produce common variations, such as 149:
A dictionary attack is based on trying all the strings in a pre-arranged listing. Such attacks originally used words found in a dictionary (hence the phrase
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US Secret Service use a distributed dictionary attack on suspect's password protecting encryption keys
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Pre-computed dictionary attacks, or "rainbow table attacks", can be thwarted by the use of
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Technique for defeating password protection using lists of likely possibilities
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infeasible, provided that the number of possible salt values is large enough.
450: 349: 326:"An off-line dictionary attack on a simple three-party key exchange protocol" 194: 178: 122: 324:
Junghyun Nam; Juryon Paik; Hyun-kyu Kang; Ung Kim; Dongho Won (2009-03-01).
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of dictionary words and storing these in a database using the hash as the
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or authentication mechanism by trying to determine its decryption key or
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is an attack using a restricted subset of a keyspace to defeat a
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Pre-computed dictionary attack/Rainbow table attack
49:. Unsourced material may be challenged and removed. 448: 155:substituting numbers for similar-looking letters 222: 109:Learn how and when to remove this message 426:– Internet Security Glossary, Version 2 165:program or manually typing a password. 449: 435:Testing for Brute Force (OWASP-AT-004) 378:. e.g., with over 1.4 billion words. 47:adding citations to reliable sources 18: 13: 284:Intercontinental Dictionary Series 14: 468: 409: 23: 286:, an online linguistic database 208:compromised by such an attack. 34:needs additional citations for 381: 369: 356: 317: 1: 310: 419:– Internet Security Glossary 173:It is possible to achieve a 144: 7: 330:IEEE Communications Letters 269: 10: 473: 223:Dictionary attack software 342:10.1109/LCOMM.2009.081609 280:E-mail address harvesting 364:"Dictionary Attacks 101" 290:Key derivation function 457:Cryptographic attacks 206:authentication system 204:for an example of an 43:improve this article 376:CrackStation's list 175:time–space tradeoff 58:"Dictionary attack" 440:2020-01-14 at the 276:Brute-force attack 254:Metasploit Project 305:Password strength 300:Password cracking 151:dictionary attack 131:dictionary attack 127:computer security 119: 118: 111: 93: 464: 403: 402: 400: 399: 385: 379: 373: 367: 360: 354: 353: 321: 163:password manager 114: 107: 103: 100: 94: 92: 51: 27: 19: 472: 471: 467: 466: 465: 463: 462: 461: 447: 446: 442:Wayback Machine 412: 407: 406: 397: 395: 393:capec.mitre.org 387: 386: 382: 374: 370: 361: 357: 322: 318: 313: 272: 244:John the Ripper 225: 171: 147: 115: 104: 98: 95: 52: 50: 40: 28: 17: 12: 11: 5: 470: 460: 459: 445: 444: 432: 427: 420: 411: 410:External links 408: 405: 404: 380: 368: 355: 336:(3): 205–207. 315: 314: 312: 309: 308: 307: 302: 297: 295:Key stretching 292: 287: 281: 278: 271: 268: 267: 266: 261: 256: 251: 246: 241: 236: 231: 224: 221: 217:precomputation 195:rainbow tables 170: 167: 146: 143: 117: 116: 31: 29: 22: 15: 9: 6: 4: 3: 2: 469: 458: 455: 454: 452: 443: 439: 436: 433: 431: 428: 425: 421: 418: 414: 413: 394: 390: 384: 377: 372: 365: 362:Jeff Atwood. 359: 351: 347: 343: 339: 335: 331: 327: 320: 316: 306: 303: 301: 298: 296: 293: 291: 288: 285: 282: 279: 277: 274: 273: 265: 262: 260: 257: 255: 252: 250: 247: 245: 242: 240: 237: 235: 232: 230: 229:Cain and Abel 227: 226: 220: 218: 214: 209: 207: 203: 200: 196: 192: 188: 184: 180: 179:pre-computing 176: 166: 164: 160: 156: 152: 142: 140: 136: 132: 128: 124: 123:cryptanalysis 113: 110: 102: 99:February 2018 91: 88: 84: 81: 77: 74: 70: 67: 63: 60: –  59: 55: 54:Find sources: 48: 44: 38: 37: 32:This article 30: 26: 21: 20: 396:. Retrieved 392: 383: 371: 358: 333: 329: 319: 210: 198: 191:disk storage 172: 150: 148: 130: 120: 105: 96: 86: 79: 72: 65: 53: 41:Please help 36:verification 33: 239:Aircrack-ng 398:2021-09-12 311:References 249:L0phtCrack 181:a list of 161:, using a 159:passphrase 139:passphrase 69:newspapers 422:RFC  415:RFC  350:1089-7798 145:Technique 451:Category 438:Archived 270:See also 264:Cryptool 259:Ophcrack 202:LM hash 83:scholar 348:  183:hashes 135:cipher 85:  78:  71:  64:  56:  234:Crack 90:JSTOR 76:books 424:4949 417:2828 346:ISSN 213:salt 129:, a 125:and 62:news 338:doi 199:See 187:key 177:by 121:In 45:by 453:: 391:. 344:. 334:13 332:. 328:. 401:. 366:. 352:. 340:: 112:) 106:( 101:) 97:( 87:· 80:· 73:· 66:· 39:.

Index


verification
improve this article
adding citations to reliable sources
"Dictionary attack"
news
newspapers
books
scholar
JSTOR
Learn how and when to remove this message
cryptanalysis
computer security
cipher
passphrase
substituting numbers for similar-looking letters
passphrase
password manager
time–space tradeoff
pre-computing
hashes
key
disk storage
rainbow tables
LM hash
authentication system
salt
precomputation
Cain and Abel
Crack

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