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Collision attack

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2192: 25: 1115:- Bishop Fox (formerly Stach & Liu). Create MD4 and MD5 hash collisions using groundbreaking new code that improves upon the techniques originally developed by Xiaoyun Wang. Using a 1.6 GHz Pentium 4, MD5 collisions can be generated in an average of 45 minutes, and MD4 collisions can be generated in an average of 5 seconds. Originally released on 22Jun2006. 449:. The rogue certificate may not be revokable by real authorities, and could also have an arbitrary forged expiry time. Even though MD5 was known to be very weak in 2004, certificate authorities were still willing to sign MD5-verified certificates in December 2008, and at least one Microsoft code-signing certificate was still using MD5 in May 2012. 336:. In this case, the attacker can choose two arbitrarily different documents, and then append different calculated values that result in the whole documents having an equal hash value. This attack is normally harder, a hash of n bits can be broken in 2 time steps, but is much more powerful than a classical collision attack. 293:
However, workarounds are possible by abusing dynamic constructs present in many formats. In this way, two documents would be created which are as similar as possible in order to have the same hash value. One document would be shown to an authority to be signed, and then the signature could be copied
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lookups. It was originally described in 2003. To execute such an attack, the attacker sends the server multiple pieces of data that hash to the same value and then tries to get the server to perform slow lookups. As the main focus of hash functions used in hash tables was speed instead of security,
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algorithms cannot sign a large amount of data efficiently, most implementations use a hash function to reduce ("compress") the amount of data that needs to be signed down to a constant size. Digital signature schemes often become vulnerable to hash collisions as soon as the underlying hash function
290:. The collision attacks against MD5 have improved so much that, as of 2007, it takes just a few seconds on a regular computer. Hash collisions created this way are usually constant length and largely unstructured, so cannot directly be applied to attack widespread document formats or protocols. 322:
files are vulnerable to collision attacks by using color value (such that text of one message is displayed with a white color that blends into the background, and text of the other message is displayed with a dark color) which can then be altered to change the signed document's
543:, one of which appeared legitimate and was submitted for signing by the RapidSSL certificate authority. The second version, which had the same MD5 hash, contained flags which signal web browsers to accept it as a legitimate authority for issuing arbitrary other certificates. 574:
are introduced, with the security objective that collisions are hard to find as long as the key is unknown. They may be slower than previous hashes, but are still much easier to compute than cryptographic hashes. As of 2021, Jean-Philippe Aumasson and
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Scott A. Crosby and Dan S. Wallach. 2003. Denial of service via algorithmic complexity attacks. In Proceedings of the 12th conference on USENIX Security Symposium - Volume 12 (SSYM'03), Vol. 12. USENIX Association, Berkeley, CA, USA,
824: 583:(2012) is the most widely-used hash function in this class. (Non-keyed "simple" hashes remain safe to use as long as the application's hash table is not controllable from the outside.) 422:
could be asked to sign a certificate for one domain, and then that certificate (specially its signature) could be used to create a new rogue certificate to impersonate another domain.
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with computing complexity between 2 and 2 and cost less than 100,000 US dollars. In 2020, researchers reduced the complexity of a chosen-prefix collision attack against SHA-1 to 2.
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to the other file. Such a malicious document would contain two different messages in the same document, but conditionally display one or the other through subtle changes to the file:
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Mallory creates two different documents A and B that have an identical hash value, i.e., a collision. Mallory seeks to deceive Bob into accepting document B, ostensibly from Alice.
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to specific hash functions. In 2007, a chosen-prefix collision attack was found against MD5, requiring roughly 2 evaluations of the MD5 function. The paper also demonstrates two
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to specific hash functions. When a collision attack is discovered and is found to be faster than a birthday attack, a hash function is often denounced as "broken". The
2172: 2002: 310:, have conditional constructs. (if-then-else) that allow testing whether a location in the file has one value or another in order to control what is displayed. 1107: 832: 271:. In a classical collision attack, the attacker has no control over the content of either message, but they are arbitrarily chosen by the algorithm. 43: 993:
Falkenberg, Andreas; Mainka, Christian; Somorovsky, Juraj; Schwenk, Jörg (2013). "A New Approach towards DoS Penetration Testing on Web Services".
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most major programming languages were affected, with new vulnerabilities of this class still showing up a decade after the original presentation.
855: 682: 1840: 524:, claiming that Alice signed B. Because the digital signature matches document B's hash, Bob's software is unable to detect the substitution. 1760: 1148: 878: 644:
we are able to find collisions for MD5 in about 2 compressions for recommended IHVs which takes approx. 6 seconds on a 2.6GHz Pentium 4.
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Alexander Sotirov; Marc Stevens; Jacob Appelbaum; Arjen Lenstra; David Molnar; Dag Arne Osvik; Benne de Weger (30 December 2008).
433:, taking advantage of a prefix collision attack against the MD5 hash function. This meant that an attacker could impersonate any 2225: 1776: 1010: 941:
Because of the way hash functions are used in the HMAC construction, the techniques used in these recent attacks do not apply
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A real-world collision attack was published in December 2008 when a group of security researchers published a forged
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files can contain cropped images, with a different part of an image being displayed without affecting the hash value.
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are not vulnerable. For the attack to be useful, the attacker must be in control of the input to the hash function.
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is practically broken; techniques like randomized (salted) hashing will buy extra time by requiring the harder
279: 1532: 1826: 1750: 979: 870: 2167: 2122: 1925: 1519: 1161: 1157: 237: 2046: 1134: 625:, Cryptology ePrint Archive Report 2004/199, 16 Aug 2004, revised 17 Aug 2004. Retrieved July 27, 2008. 916:"SHA-1 is a Shambles - First Chosen-Prefix Collision on SHA-1 and Application to the PGP Web of Trust" 2162: 1415: 1220: 737: 693: 663: 2152: 2142: 1997: 1755: 1591: 1290: 1285: 713: 537: 434: 303: 282:
was largely induced by published collision attacks against two very commonly used hash functions,
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of its components by a Microsoft root certificate that still used the compromised MD5 algorithm.
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An extension of the collision attack is the chosen-prefix collision attack, which is specific to
1935: 1878: 1786: 1172: 540: 2195: 2041: 1987: 1801: 1451: 1405: 1295: 1253: 1238: 724: 650: 533: 430: 419: 753:"Chosen-Prefix Collisions for MD5 and Colliding X.509 Certificates for Different Identities" 2157: 2081: 1471: 1375: 1325: 1300: 760: 514:, who agrees to what the document says, signs its hash, and sends the signature to Mallory. 476: 229: 752: 39: 8: 1910: 1796: 1673: 1622: 1561: 1461: 1380: 1340: 1320: 1066: 971: 599: 576: 571: 446: 764: 2026: 2010: 1952: 1730: 1714: 1663: 1248: 1016: 456:
malware successfully used a new variation of a chosen-prefix collision attack to spoof
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certificates for different domain names, with colliding hash values. This means that a
233: 83: 1108:"Meaningful Collisions", attack scenarios for exploiting cryptographic hash collisions 2086: 2076: 1942: 1607: 1006: 778: 562:
attack that uses hash collisions to exploit the worst-case (linear probe) runtime of
559: 492: 438: 1020: 2021: 1873: 1694: 1410: 998: 768: 245: 856:"CWI Cryptanalist Discovers New Cryptographic Attack Variant in Flame Spy Malware" 714:"A Note on the Practical Value of Single Hash Collisions for Special File Formats" 1709: 1658: 1653: 1441: 1156: 960: 889: 497: 453: 241: 91: 773: 570:
To prevent hash flooding without making the hash function overly complex, newer
2096: 2016: 1972: 1915: 1900: 1699: 1427: 307: 87: 936: 2214: 2177: 2132: 2091: 2071: 1962: 1920: 1895: 1791: 1668: 803: 411: 404: 275: 216: 1370: 973: 953: 2127: 1967: 1957: 1947: 1905: 1849: 678: 587: 457: 75: 2106: 1781: 1627: 1556: 1552: 1070: 1064: 1002: 879:"SHA-1 collision attacks are now actually practical and a looming danger" 442: 711: 2066: 2036: 2031: 1992: 915: 898:"From Collisions to Chosen-Prefix Collisions Application to Full SHA-1" 897: 750: 563: 299: 255:
Mathematically stated, a collision attack finds two different messages
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bits can be broken in 2 time steps (evaluations of the hash function).
248:, these attacks are much faster than a brute force would be. A hash of 1088: 2056: 1456: 1335: 828: 687: 1243: 1087:
Gerbet, Thomas; Kumar, Amrit; Lauradoux, Cédric (12 November 2014).
1037: 479:, thus collision attacks do not affect their security. For example, 463:
In 2019, researchers found a chosen-prefix collision attack against
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In 2008, researchers used a chosen-prefix collision attack against
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provides insufficient context for those unfamiliar with the subject
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Many applications of cryptographic hash functions do not rely on
759:. Lecture Notes in Computer Science. Vol. 4515. p. 1. 1977: 1740: 1481: 1476: 1446: 1436: 1395: 1390: 1385: 1365: 1360: 1330: 1315: 1275: 712:
Max Gebhardt; Georg Illies; Werner Schindler (4 January 2017).
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tries to find two inputs producing the same hash value, i.e. a
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Mallory attaches the signature from document A to document B.
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Collisions for Hash Functions MD4, MD5, HAVAL-128 and RIPEMD
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Marc Stevens; Arjen Lenstra; Benne de Weger (2007-11-30).
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It is possible to perform an analogous attack to fill up
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signing certificate that could be used to impersonate a
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2013 IEEE 20th International Conference on Web Services
935:. Cryptography Research Inc. 2005-02-15. Archived from 2003:
Cryptographically secure pseudorandom number generator
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More efficient attacks are also possible by employing
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Mathematically stated, given two different prefixes
700: 676: 621:Xiaoyun Wang, Dengguo Feng, Xuejia Lai, Hongbo Yu: 97:There are roughly two types of collision attacks: 797: 327: 274:More efficient attacks are possible by employing 94:where a specific target hash value is specified. 2212: 876: 683:"Hash Collisions (The Poisoned Message Attack)" 240:is inherently vulnerable to collisions using a 825:"Microsoft releases Security Advisory 2718704" 744: 634: 1834: 1142: 925: 798:Alexander Sotirov; et al. (2008-12-30). 223: 914:Gaëtan Leurent; Thomas Peyrin (2020-01-05). 896:Gaëtan Leurent; Thomas Peyrin (2019-05-06). 853: 536:certificate. They created two versions of a 1841: 1827: 1149: 1135: 1090:The Power of Evil Choices in Bloom Filters 617: 615: 503:The usual attack scenario goes like this: 954:Randomized Hashing and Digital Signatures 772: 522:sends the signature and document B to Bob 62:Learn how and when to remove this message 532:using this scenario, to produce a rogue 1058: 757:Advances in Cryptology - EUROCRYPT 2007 612: 2213: 1822: 1130: 1113:Fast MD5 and MD4 Collision Generators 1032: 1030: 486: 44:providing more context for the reader 858:. Centrum Wiskunde & Informatica 18: 590:using a (partial) preimage attack. 470: 13: 1027: 14: 2237: 1101: 1071:"SipHash: a fast short-input PRF" 800:"Creating a rogue CA certificate" 2191: 2190: 1848: 546: 353:, the attack finds two suffixes 23: 1080: 1048: 986: 965: 952:Shai Halevi and Hugo Krawczyk, 946: 2052:Information-theoretic security 1746:NIST hash function competition 877:Catalin Cimpanu (2019-05-13). 847: 817: 791: 670: 628: 328:Chosen-prefix collision attack 280:NIST hash function competition 148:Chosen-prefix collision attack 1: 1065:Jean-Philippe Aumasson & 831:. 3 June 2012. Archived from 605: 334:Merkle–Damgård hash functions 151:Given two different prefixes 2226:Cryptographic hash functions 1751:Password Hashing Competition 1162:message authentication codes 1158:Cryptographic hash functions 980:Chaos Communication Congress 975:MD5 considered harmful today 854:Marc Stevens (7 June 2012). 635:M.M.J. Stevens (June 2007). 104:Find two different messages 7: 2168:Message authentication code 2123:Cryptographic hash function 1926:Cryptographic hash function 1705:Merkle–Damgård construction 774:10.1007/978-3-540-72540-4_1 593: 298:Some document formats like 238:cryptographic hash function 90:. This is in contrast to a 10: 2242: 2047:Harvest now, decrypt later 224:Classical collision attack 101:Classical collision attack 2186: 2163:Post-quantum cryptography 2115: 1856: 1818: 1769: 1723: 1687: 1641: 1590: 1518: 1495: 1424: 1268: 1229: 1191: 1168: 1126: 1122: 1093:(report). INRIA Grenoble. 512:sends document A to Alice 2153:Quantum key distribution 2143:Authenticated encryption 1998:Random number generation 1499:key derivation functions 933:"Hash Collision Q&A" 2148:Public-key cryptography 2138:Symmetric-key algorithm 1931:Key derivation function 1891:Cryptographic primitive 1884:Authentication protocol 1869:Outline of cryptography 1864:History of cryptography 1777:Hash-based cryptography 1679:Length extension attack 637:"On Collisions for MD5" 215:), where ∥ denotes the 1936:Secure Hash Algorithms 1879:Cryptographic protocol 1787:Message authentication 732:Cite journal requires 658:Cite journal requires 541:public key certificate 437:-secured website as a 2221:Cryptographic attacks 2042:End-to-end encryption 1988:Cryptojacking malware 534:certificate authority 431:certificate authority 420:certificate authority 230:symmetric-key ciphers 2158:Quantum cryptography 2082:Trusted timestamping 1003:10.1109/ICWS.2013.72 997:. pp. 491–498. 572:keyed hash functions 477:collision resistance 165:, find two suffixes 16:Cryptographic attack 1911:Cryptographic nonce 1674:Side-channel attack 1067:Daniel J. Bernstein 765:2007LNCS.4515....1S 600:Puzzle friendliness 577:Daniel J. Bernstein 447:electronic commerce 234:brute force attacks 40:improve the article 2027:Subliminal channel 2011:Pseudorandom noise 1953:Key (cryptography) 1731:CAESAR Competition 1715:HAIFA construction 1664:Brute-force attack 959:2009-06-20 at the 487:Digital signatures 403:) (where ∥ is the 232:are vulnerable to 84:cryptographic hash 2208: 2207: 2204: 2203: 2087:Key-based routing 2077:Trapdoor function 1943:Digital signature 1814: 1813: 1810: 1809: 1608:ChaCha20-Poly1305 1425:Password hashing/ 1012:978-0-7695-5025-1 784:978-3-540-72539-8 690:2005 rump session 560:denial of service 493:digital signature 439:man-in-the-middle 72: 71: 64: 2233: 2194: 2193: 2022:Insecure channel 1874:Classical cipher 1843: 1836: 1829: 1820: 1819: 1695:Avalanche effect 1649:Collision attack 1192:Common functions 1151: 1144: 1137: 1128: 1127: 1124: 1123: 1120: 1119: 1095: 1094: 1084: 1078: 1077: 1075: 1062: 1056: 1052: 1046: 1045: 1034: 1025: 1024: 990: 984: 983: 969: 963: 950: 944: 943: 929: 923: 922: 920: 911: 905: 904: 902: 893: 887: 886: 874: 868: 867: 865: 863: 851: 845: 844: 842: 840: 821: 815: 814: 812: 811: 802:. Archived from 795: 789: 788: 776: 748: 742: 741: 735: 730: 728: 720: 718: 709: 698: 697: 692:. Archived from 674: 668: 667: 661: 656: 654: 646: 641: 632: 626: 619: 471:Attack scenarios 246:birthday problem 144:More generally: 80:collision attack 67: 60: 56: 53: 47: 27: 26: 19: 2241: 2240: 2236: 2235: 2234: 2232: 2231: 2230: 2211: 2210: 2209: 2200: 2182: 2111: 1852: 1847: 1806: 1765: 1724:Standardization 1719: 1710:Sponge function 1683: 1659:Birthday attack 1654:Preimage attack 1637: 1593: 1586: 1514: 1497: 1496:General purpose 1491: 1426: 1420: 1269:Other functions 1264: 1231:SHA-3 finalists 1225: 1187: 1164: 1155: 1104: 1099: 1098: 1085: 1081: 1073: 1063: 1059: 1053: 1049: 1036: 1035: 1028: 1013: 991: 987: 970: 966: 961:Wayback Machine 951: 947: 939:on 2008-07-17. 931: 930: 926: 918: 912: 908: 900: 894: 890: 875: 871: 861: 859: 852: 848: 838: 836: 823: 822: 818: 809: 807: 796: 792: 785: 749: 745: 733: 731: 722: 721: 716: 710: 701: 675: 671: 659: 657: 648: 647: 639: 633: 629: 620: 613: 608: 596: 554:(also known as 549: 498:preimage attack 489: 473: 402: 395: 384: 377: 366: 359: 352: 345: 330: 242:birthday attack 226: 214: 207: 196: 189: 178: 171: 164: 157: 139: 128: 117: 110: 92:preimage attack 68: 57: 51: 48: 37: 28: 24: 17: 12: 11: 5: 2239: 2229: 2228: 2223: 2206: 2205: 2202: 2201: 2199: 2198: 2187: 2184: 2183: 2181: 2180: 2175: 2173:Random numbers 2170: 2165: 2160: 2155: 2150: 2145: 2140: 2135: 2130: 2125: 2119: 2117: 2113: 2112: 2110: 2109: 2104: 2099: 2097:Garlic routing 2094: 2089: 2084: 2079: 2074: 2069: 2064: 2059: 2054: 2049: 2044: 2039: 2034: 2029: 2024: 2019: 2017:Secure channel 2014: 2008: 2007: 2006: 1995: 1990: 1985: 1980: 1975: 1973:Key stretching 1970: 1965: 1960: 1955: 1950: 1945: 1940: 1939: 1938: 1933: 1928: 1918: 1916:Cryptovirology 1913: 1908: 1903: 1901:Cryptocurrency 1898: 1893: 1888: 1887: 1886: 1876: 1871: 1866: 1860: 1858: 1854: 1853: 1846: 1845: 1838: 1831: 1823: 1816: 1815: 1812: 1811: 1808: 1807: 1805: 1804: 1799: 1794: 1789: 1784: 1779: 1773: 1771: 1767: 1766: 1764: 1763: 1758: 1753: 1748: 1743: 1738: 1733: 1727: 1725: 1721: 1720: 1718: 1717: 1712: 1707: 1702: 1700:Hash collision 1697: 1691: 1689: 1685: 1684: 1682: 1681: 1676: 1671: 1666: 1661: 1656: 1651: 1645: 1643: 1639: 1638: 1636: 1635: 1630: 1625: 1620: 1615: 1610: 1605: 1599: 1597: 1588: 1587: 1585: 1584: 1579: 1574: 1569: 1564: 1559: 1550: 1545: 1540: 1535: 1530: 1524: 1522: 1516: 1515: 1513: 1512: 1509: 1503: 1501: 1493: 1492: 1490: 1489: 1484: 1479: 1474: 1469: 1464: 1459: 1454: 1449: 1444: 1439: 1433: 1431: 1428:key stretching 1422: 1421: 1419: 1418: 1413: 1408: 1403: 1398: 1393: 1388: 1383: 1378: 1373: 1368: 1363: 1358: 1353: 1348: 1343: 1338: 1333: 1328: 1323: 1318: 1313: 1308: 1303: 1298: 1293: 1288: 1283: 1278: 1272: 1270: 1266: 1265: 1263: 1262: 1256: 1251: 1246: 1241: 1235: 1233: 1227: 1226: 1224: 1223: 1218: 1213: 1208: 1202: 1195: 1193: 1189: 1188: 1186: 1185: 1180: 1175: 1169: 1166: 1165: 1154: 1153: 1146: 1139: 1131: 1117: 1116: 1110: 1103: 1102:External links 1100: 1097: 1096: 1079: 1069:(2012-09-18). 1057: 1047: 1026: 1011: 985: 964: 945: 924: 906: 888: 869: 846: 835:on 7 June 2012 816: 790: 783: 743: 734:|journal= 699: 696:on 2010-03-27. 669: 660:|journal= 627: 610: 609: 607: 604: 603: 602: 595: 592: 548: 545: 526: 525: 518: 515: 508: 488: 485: 472: 469: 400: 393: 382: 375: 364: 357: 350: 343: 329: 326: 325: 324: 317: 311: 308:Microsoft Word 225: 222: 221: 220: 212: 205: 194: 187: 176: 169: 162: 155: 149: 142: 141: 137: 126: 115: 108: 102: 88:hash collision 70: 69: 31: 29: 22: 15: 9: 6: 4: 3: 2: 2238: 2227: 2224: 2222: 2219: 2218: 2216: 2197: 2189: 2188: 2185: 2179: 2178:Steganography 2176: 2174: 2171: 2169: 2166: 2164: 2161: 2159: 2156: 2154: 2151: 2149: 2146: 2144: 2141: 2139: 2136: 2134: 2133:Stream cipher 2131: 2129: 2126: 2124: 2121: 2120: 2118: 2114: 2108: 2105: 2103: 2100: 2098: 2095: 2093: 2092:Onion routing 2090: 2088: 2085: 2083: 2080: 2078: 2075: 2073: 2072:Shared secret 2070: 2068: 2065: 2063: 2060: 2058: 2055: 2053: 2050: 2048: 2045: 2043: 2040: 2038: 2035: 2033: 2030: 2028: 2025: 2023: 2020: 2018: 2015: 2012: 2009: 2004: 2001: 2000: 1999: 1996: 1994: 1991: 1989: 1986: 1984: 1981: 1979: 1976: 1974: 1971: 1969: 1966: 1964: 1963:Key generator 1961: 1959: 1956: 1954: 1951: 1949: 1946: 1944: 1941: 1937: 1934: 1932: 1929: 1927: 1924: 1923: 1922: 1921:Hash function 1919: 1917: 1914: 1912: 1909: 1907: 1904: 1902: 1899: 1897: 1896:Cryptanalysis 1894: 1892: 1889: 1885: 1882: 1881: 1880: 1877: 1875: 1872: 1870: 1867: 1865: 1862: 1861: 1859: 1855: 1851: 1844: 1839: 1837: 1832: 1830: 1825: 1824: 1821: 1817: 1803: 1800: 1798: 1795: 1793: 1792:Proof of work 1790: 1788: 1785: 1783: 1780: 1778: 1775: 1774: 1772: 1768: 1762: 1759: 1757: 1754: 1752: 1749: 1747: 1744: 1742: 1739: 1737: 1734: 1732: 1729: 1728: 1726: 1722: 1716: 1713: 1711: 1708: 1706: 1703: 1701: 1698: 1696: 1693: 1692: 1690: 1686: 1680: 1677: 1675: 1672: 1670: 1669:Rainbow table 1667: 1665: 1662: 1660: 1657: 1655: 1652: 1650: 1647: 1646: 1644: 1640: 1634: 1631: 1629: 1626: 1624: 1621: 1619: 1616: 1614: 1611: 1609: 1606: 1604: 1601: 1600: 1598: 1595: 1592:Authenticated 1589: 1583: 1580: 1578: 1575: 1573: 1570: 1568: 1565: 1563: 1560: 1558: 1554: 1551: 1549: 1546: 1544: 1541: 1539: 1536: 1534: 1531: 1529: 1526: 1525: 1523: 1521: 1520:MAC functions 1517: 1510: 1508: 1505: 1504: 1502: 1500: 1494: 1488: 1485: 1483: 1480: 1478: 1475: 1473: 1470: 1468: 1465: 1463: 1460: 1458: 1455: 1453: 1450: 1448: 1445: 1443: 1440: 1438: 1435: 1434: 1432: 1429: 1423: 1417: 1414: 1412: 1409: 1407: 1404: 1402: 1399: 1397: 1394: 1392: 1389: 1387: 1384: 1382: 1379: 1377: 1374: 1372: 1369: 1367: 1364: 1362: 1359: 1357: 1354: 1352: 1349: 1347: 1344: 1342: 1339: 1337: 1334: 1332: 1329: 1327: 1324: 1322: 1319: 1317: 1314: 1312: 1309: 1307: 1304: 1302: 1299: 1297: 1294: 1292: 1289: 1287: 1284: 1282: 1279: 1277: 1274: 1273: 1271: 1267: 1260: 1257: 1255: 1252: 1250: 1247: 1245: 1242: 1240: 1237: 1236: 1234: 1232: 1228: 1222: 1219: 1217: 1214: 1212: 1209: 1207:(compromised) 1206: 1203: 1201:(compromised) 1200: 1197: 1196: 1194: 1190: 1184: 1183:Known attacks 1181: 1179: 1176: 1174: 1171: 1170: 1167: 1163: 1159: 1152: 1147: 1145: 1140: 1138: 1133: 1132: 1129: 1125: 1121: 1114: 1111: 1109: 1106: 1105: 1092: 1091: 1083: 1072: 1068: 1061: 1051: 1043: 1039: 1033: 1031: 1022: 1018: 1014: 1008: 1004: 1000: 996: 989: 981: 977: 976: 968: 962: 958: 955: 949: 942: 938: 934: 928: 917: 910: 899: 892: 884: 880: 873: 857: 850: 834: 830: 826: 820: 806:on 2012-04-18 805: 801: 794: 786: 780: 775: 770: 766: 762: 758: 754: 747: 739: 726: 715: 708: 706: 704: 695: 691: 689: 684: 680: 677:Magnus Daum; 673: 665: 652: 645: 638: 631: 624: 618: 616: 611: 601: 598: 597: 591: 589: 588:Bloom filters 584: 582: 578: 573: 568: 565: 561: 557: 553: 552:Hash flooding 547:Hash flooding 544: 542: 539: 535: 531: 523: 520:Mallory then 519: 516: 513: 509: 506: 505: 504: 501: 499: 494: 484: 482: 478: 468: 466: 461: 459: 455: 450: 448: 444: 440: 436: 432: 428: 423: 421: 417: 413: 412:cryptanalysis 408: 406: 405:concatenation 399: 392: 388: 381: 374: 370: 363: 356: 349: 342: 337: 335: 321: 318: 315: 312: 309: 305: 301: 297: 296: 295: 291: 289: 285: 281: 277: 276:cryptanalysis 272: 270: 266: 262: 258: 253: 251: 247: 244:. Due to the 243: 239: 235: 231: 218: 217:concatenation 211: 204: 200: 193: 186: 182: 175: 168: 161: 154: 150: 147: 146: 145: 136: 132: 125: 121: 114: 107: 103: 100: 99: 98: 95: 93: 89: 85: 81: 77: 66: 63: 55: 52:February 2020 45: 41: 35: 32:This article 30: 21: 20: 2128:Block cipher 1968:Key schedule 1958:Key exchange 1948:Kleptography 1906:Cryptosystem 1850:Cryptography 1648: 1089: 1082: 1060: 1050: 1041: 994: 988: 974: 967: 948: 940: 937:the original 927: 909: 891: 882: 872: 860:. Retrieved 849: 837:. Retrieved 833:the original 819: 808:. Retrieved 804:the original 793: 756: 746: 725:cite journal 694:the original 686: 679:Stefan Lucks 672: 651:cite journal 643: 630: 585: 569: 555: 551: 550: 527: 521: 511: 502: 490: 474: 462: 458:code signing 451: 424: 409: 407:operation). 397: 390: 386: 379: 372: 368: 361: 354: 347: 340: 338: 331: 292: 273: 268: 264: 263:, such that 260: 256: 254: 249: 227: 209: 202: 198: 191: 184: 180: 173: 166: 159: 152: 143: 134: 130: 123: 119: 112: 105: 96: 79: 76:cryptography 73: 58: 49: 38:Please help 33: 2116:Mathematics 2107:Mix network 1782:Merkle tree 1770:Utilization 1756:NSA Suite B 445:to protect 443:web browser 2215:Categories 2067:Ciphertext 2037:Decryption 2032:Encryption 1993:Ransomware 1594:encryption 1371:RadioGatún 1178:Comparison 810:2009-10-07 606:References 564:hash table 367:such that 300:PostScript 228:Much like 219:operation. 179:such that 118:such that 2057:Plaintext 1511:KDF1/KDF2 1430:functions 1416:Whirlpool 829:Microsoft 688:Eurocrypt 2196:Category 2102:Kademlia 2062:Codetext 2005:(CSPRNG) 1983:Machines 1736:CRYPTREC 1567:Poly1305 1487:yescrypt 1401:Streebog 1281:CubeHash 1261:(winner) 1021:17805370 957:Archived 594:See also 510:Mallory 491:Because 323:content. 269:hash(m2) 265:hash(m1) 236:, every 1857:General 1642:Attacks 1572:SipHash 1528:CBC-MAC 1462:LM hash 1442:Balloon 1306:HAS-160 761:Bibcode 581:SipHash 558:) is a 556:HashDoS 1978:Keygen 1802:Pepper 1741:NESSIE 1688:Design 1482:scrypt 1477:PBKDF2 1452:Catena 1447:bcrypt 1437:Argon2 1396:Snefru 1391:Shabal 1386:SWIFFT 1366:RIPEMD 1361:N-hash 1336:MASH-2 1331:MASH-1 1316:Kupyna 1276:BLAKE3 1259:Keccak 1244:Grøstl 1221:BLAKE2 1042:v8.dev 1019:  1009:  862:9 June 839:4 June 781:  304:macros 2013:(PRN) 1596:modes 1472:Makwa 1467:Lyra2 1457:crypt 1406:Tiger 1356:MDC-2 1311:HAVAL 1296:Fugue 1254:Skein 1239:BLAKE 1216:SHA-3 1211:SHA-2 1205:SHA-1 1074:(PDF) 1017:S2CID 982:2008. 919:(PDF) 901:(PDF) 883:ZDNet 717:(PDF) 640:(PDF) 481:HMACs 465:SHA-1 454:Flame 427:X.509 416:X.509 302:, or 288:SHA-1 82:on a 1797:Salt 1761:CNSA 1628:IAPM 1582:VMAC 1577:UMAC 1562:PMAC 1557:CMAC 1553:OMAC 1548:NMAC 1543:HMAC 1538:GMAC 1507:HKDF 1376:SIMD 1326:Lane 1301:GOST 1286:ECOH 1173:List 1160:and 1055:3-3. 1007:ISBN 864:2012 841:2012 779:ISBN 738:help 664:help 452:The 387:hash 385:) = 369:hash 360:and 314:TIFF 286:and 259:and 199:hash 197:) = 181:hash 172:and 158:and 131:hash 129:) = 120:hash 111:and 78:, a 1633:OCB 1623:GCM 1618:EAX 1613:CWC 1603:CCM 1533:DAA 1411:VSH 1381:SM3 1351:MD6 1346:MD4 1341:MD2 1321:LSH 1291:FSB 1199:MD5 999:doi 769:doi 579:'s 538:TLS 530:MD5 435:SSL 320:PDF 306:in 284:MD5 74:In 42:by 2217:: 1249:JH 1040:. 1029:^ 1015:. 1005:. 978:. 881:. 827:. 777:. 767:. 755:. 729:: 727:}} 723:{{ 702:^ 685:. 681:. 655:: 653:}} 649:{{ 642:. 614:^ 500:. 396:∥ 378:∥ 346:, 267:= 261:m2 257:m1 208:∥ 190:∥ 140:). 1842:e 1835:t 1828:v 1555:/ 1150:e 1143:t 1136:v 1076:. 1044:. 1023:. 1001:: 921:. 903:. 885:. 866:. 843:. 813:. 787:. 771:: 763:: 740:) 736:( 719:. 666:) 662:( 401:2 398:s 394:2 391:p 389:( 383:1 380:s 376:1 373:p 371:( 365:2 362:s 358:1 355:s 351:2 348:p 344:1 341:p 250:n 213:2 210:s 206:2 203:p 201:( 195:1 192:s 188:1 185:p 183:( 177:2 174:s 170:1 167:s 163:2 160:p 156:1 153:p 138:2 135:m 133:( 127:1 124:m 122:( 116:2 113:m 109:1 106:m 65:) 59:( 54:) 50:( 46:. 36:.

Index

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cryptography
cryptographic hash
hash collision
preimage attack
concatenation
symmetric-key ciphers
brute force attacks
cryptographic hash function
birthday attack
birthday problem
cryptanalysis
NIST hash function competition
MD5
SHA-1
PostScript
macros
Microsoft Word
TIFF
PDF
Merkle–Damgård hash functions
concatenation
cryptanalysis
X.509
certificate authority
X.509
certificate authority
SSL

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