Hash function security summary

This article summarizes publicly known attacks against cryptographic hash functions. Note that not all entries may be up to date. For a summary of other hash function parameters, see comparison of cryptographic hash functions.

Table color key

  No known successful attacks — attack only breaks a reduced version of the hash

  Theoretical break — attack breaks all rounds and has lower complexity than security claim

  Attack demonstrated in practice

Common hash functions

Collision resistance

Hash function	Security claim	Best attack	Publish date	Comment
MD5	2^64	2^18 time	2013-03-25	This attack takes seconds on a regular PC. Two-block collisions in 2^18, single-block collisions in 2^41.[1]
SHA-1	2^80	2^60.3 ... 2^65.3	2012-06-19	Paper.[2] Attack is feasible with large amounts of computation power.[3]
SHA256	2^128	31 of 64 rounds (2^65.5)	2013-05-28	Two-block collision.[4]
SHA512	2^256	24 of 80 rounds (2^32.5)	2008-11-25	Paper.[5]

Chosen prefix collision attack

Hash function	Security claim	Best attack	Publish date	Comment
MD5	2^64	2^39	2009-06-16	This attack takes hours on a regular PC.[6]
SHA-1	2^80	2^77.1	2012-06-19	Paper.[2]
SHA256	2^128
SHA512	2^256

Preimage resistance

Hash function	Security claim	Best attack	Publish date	Comment
MD5	2^128	2^123.4	2009-04-27	Paper.[7]
SHA-1	2^160	45 of 80 rounds	2008-08-17	Paper.[8]
SHA256	2^256	43 of 64 rounds (2^254.9 time, 2^6 memory)	2009-12-10	Paper.[9]
SHA512	2^512	46 of 80 rounds (2^511.5 time, 2^6 memory)	2008-11-25	Paper,[10] updated version.[9]

Less common hash functions

Collision resistance

Hash function	Security claim	Best attack	Publish date	Comment
GOST	2^128	2^105	2008-08-18	Paper.[11]
HAVAL-128	2^64	2^7	2004-08-17	Collisions originally reported in 2004,[12] followed up by cryptanalysis paper in 2005.[13]
MD2	2^64	2^63.3 time, 2^52 memory	2009	Slightly less computationally expensive than a birthday attack,[14] but for practical purposes, memory requirements make it more expensive.
MD4	2^64	3 operations	2007-03-22	Finding collisions almost as fast as verifying them.[15]
PANAMA	2^128	2^6	2007-04-04	Paper,[16] improvement of an earlier theoretical attack from 2001.[17]
RIPEMD (original)	2^64	2^18 time	2004-08-17	Collisions originally reported in 2004,[12] followed up by cryptanalysis paper in 2005.[18]
RadioGatún	2^608 *	2^704	2008-12-04	For a word size w between 1-64 bits, the hash provides a collision security claim of 2^8.5w. For any value, the attack can find a collision in 2^11w time.[19]
RIPEMD-160	2^80	48 of 80 rounds (2^51 time)	2006	Paper.[20]
SHA-0	2^80	2^33.6 time	2008-02-11	Two-block collisions using boomerang attack. Attack takes estimated 1 hour on an average PC.[21]
Streebog	2^256	9.5 rounds of 12 (2^176 time, 2^128 memory)	2013-09-10	Rebound attack.[22]
Whirlpool	2^256	4.5 of 10 rounds (2^120 time)	2009-02-24	Rebound attack.[23]

Preimage resistance

Hash function	Security claim	Best attack	Publish date	Comment
GOST	2^256	2^192	2008-08-18	Paper.[11]
MD2	2^128	2^73 time, 2^73 memory	2008	Paper.[24]
MD4	2^128	2^102 time, 2^33 memory	2008-02-10	Paper.[25]
RIPEMD (original)	2^128	35 of 48 rounds	2011	Paper.[26]
RIPEMD-128	2^128	35 of 64 rounds
RIPEMD-160	2^160	31 or 80 rounds
Streebog	2^512	2^266 time, 2^259 data	2014-08-29	The paper presents two second-preimage attacks with variable data requirements.[27]
Tiger	2^192	2^188.8 time, 2^8 memory	2010-12-06	Paper.[28]

See also

• Comparison of cryptographic hash functions
• Cryptographic hash function
• Collision attack
• Preimage attack
• Cipher security summary

References

1. Tao Xie, Fanbao Liu, Dengguo Feng (25 March 2013). "Fast Collision Attack on MD5".
2. Marc Stevens (2012-06-19). "Attacks on Hash Functions and Applications" (PDF). PhD thesis.
3. Bruce Schneier (2012-10-05). "When Will We See Collisions for SHA-1?".
4. Florian Mendel, Tomislav Nad, Martin Schläffer (2013-05-28). Improving Local Collisions: New Attacks on Reduced SHA-256. Eurocrypt 2013.
5. Somitra Kumar Sanadhya, Palash Sarkar (2008-11-25). New Collision Attacks against Up to 24-Step SHA-2. Indocrypt 2008.
6. Marc Stevens, Arjen Lenstra, Benne de Weger (2009-06-16). "Chosen-prefix Collisions for MD5 and Applications" (PDF).
7. Yu Sasaki, Kazumaro Aoki (2009-04-27). Finding Preimages in Full MD5 Faster Than Exhaustive Search. Eurocrypt 2009.
8. Christophe De Cannière, Christian Rechberger (2008-08-17). Preimages for Reduced SHA-0 and SHA-1. Crypto 2008.
9. Kazumaro Aoki, Jian Guo, Krystian Matusiewicz, Yu Sasaki, Lei Wang (2009-12-10). Preimages for Step-Reduced SHA-2. Asiacrypt 2009.
10. Yu Sasaki, Lei Wang, and Kazumaro Aoki (2008-11-25). "Preimage Attacks on 41-Step SHA-256 and 46-Step SHA-512".
11. Florian Mendel, Norbert Pramstaller, Christian Rechberger, Marcin Kontak, Janusz Szmidt (2008-08-18). Cryptanalysis of the GOST Hash Function. Crypto 2008.
12. Xiaoyun Wang, Dengguo Feng, Xuejia Lai, Hongbo Yu (2004-08-17). "Collisions for Hash Functions MD4, MD5, HAVAL-128 and RIPEMD".
13. Xiaoyun Wang, Dengguo Feng, Xiuyuan Yu (October 2005). "An attack on hash function HAVAL-128" (PDF). Science in China Series F: Information Sciences 48 (5): 545–556.
14. Lars R. Knudsen, John Erik Mathiassen, Frédéric Muller, Søren S. Thomsen (January 2010). "Cryptanalysis of MD2". Journal of Cryptology 23 (1): 72–90. doi:10.1007/s00145-009-9054-1.
15. Yu Sasaki, Yusuke Naito, Noboru Kunihiro, Kazuo Ohta (2007-03-22). "Improved Collision Attacks on MD4 and MD5". IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences. E90-A (1): 36–47. doi:10.1093/ietfec/e90-a.1.36.
16. Joan Daemen, Gilles Van Assche (2007-04-04). Producing Collisions for Panama, Instantaneously. FSE 2007.
17. Vincent Rijmen, Bart Van Rompay, Bart Preneel, Joos Vandewalle (2001). Producing Collisions for PANAMA. FSE 2001.
18. Xiaoyun Wang, Xuejia Lai, Dengguo Feng, Hui Chen, Xiuyuan Yu (2005-05-23). Cryptanalysis of the Hash Functions MD4 and RIPEMD. Eurocrypt 2005.
19. Thomas Fuhr, Thomas Peyrin (2008-12-04). Cryptanalysis of RadioGatun. FSE 2009.
20. Florian Mendel, Norbert Pramstaller, Christian Rechberger, Vincent Rijmen (2006). On the Collision Resistance of RIPEMD-160. ISC 2006.
21. Stéphane Manuel, Thomas Peyrin (2008-02-11). Collisions on SHA-0 in One Hour. FSE 2008.
22. Zongyue Wang, Hongbo Yu, Xiaoyun Wang (2013-09-10). "Cryptanalysis of GOST R hash function". Information Processing Letters 114 (12): 655–662. doi:10.1016/j.ipl.2014.07.007.
23. Florian Mendel, Christian Rechberger, Martin Schläffer, Søren S. Thomsen (2009-02-24). The Rebound Attack: Cryptanalysis of Reduced Whirlpool and Grøstl (PDF). FSE 2009.
24. Søren S. Thomsen (2008). "An improved preimage attack on MD2".
25. Gaëtan Leurent (2008-02-10). MD4 is Not One-Way (PDF). FSE 2008.
26. Chiaki Ohtahara, Yu Sasaki, Takeshi Shimoyama (2011). Preimage Attacks on Step-Reduced RIPEMD-128 and RIPEMD-160. ISC 2011.
27. Jian Guo, Jérémy Jean, Gaëtan Leurent, Thomas Peyrin, Lei Wang (2014-08-29). The Usage of Counter Revisited: Second-Preimage Attack on New Russian Standardized Hash Function. SAC 2014.
28. Jian Guo, San Ling, Christian Rechberger, Huaxiong Wang (2010-12-06). Advanced Meet-in-the-Middle Preimage Attacks: First Results on Full Tiger, and Improved Results on MD4 and SHA-2. Asiacrypt 2010. pp. 12–17.

External links

• 2010 summary of attacks against Tiger, MD4 and SHA-2: Jian Guo, San Ling, Christian Rechberger, Huaxiong Wang (2010-12-06). Advanced Meet-in-the-Middle Preimage Attacks: First Results on Full Tiger, and Improved Results on MD4 and SHA-2. Asiacrypt 2010. p. 3.