Is it feasible to get a hash collision for CRC32, MD-5 and SHA-1 on one file?How hard is it to generate a simultaneous MD5 and SHA1 collision?Brute forcing CRC-32Is Dropbox's hashing method cryptographically secure?Is there a generic attack on encrypted CRC32 when used as a MAC?CRC32 vs. low 32 bits of cryptographic hashIntegrity compromised - HASH modifiedWould SHA-1 be safe for certificates with short validity?Checksum vs. non-cryptographic hashHow does the attack on MD5 work that allows a file to show its own (full) hash?How is it possible to detect “unknown SHA-1 cryptanalytic collision attacks given just a single file from a colliding file pair”?

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Is it feasible to get a hash collision for CRC32, MD-5 and SHA-1 on one file?

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Is it feasible to get a hash collision for CRC32, MD-5 and SHA-1 on one file?


How hard is it to generate a simultaneous MD5 and SHA1 collision?Brute forcing CRC-32Is Dropbox's hashing method cryptographically secure?Is there a generic attack on encrypted CRC32 when used as a MAC?CRC32 vs. low 32 bits of cryptographic hashIntegrity compromised - HASH modifiedWould SHA-1 be safe for certificates with short validity?Checksum vs. non-cryptographic hashHow does the attack on MD5 work that allows a file to show its own (full) hash?How is it possible to detect “unknown SHA-1 cryptanalytic collision attacks given just a single file from a colliding file pair”?






.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;








4












$begingroup$


I'm aware that individually, each has its weaknesses (especially CRC32), but is it feasible that a file could be created to falsely match all three?










share|improve this question









$endgroup$




migrated from superuser.com 9 hours ago


This question came from our site for computer enthusiasts and power users.


















  • $begingroup$
    I think it would be difficult to actively intend to get a simultaneous clash on all three given that they use different algorithms. Clashes are possible in each, sure, and you can engineer a clash in each if you are determined but I would have thought it would be difficult to get a clash in all three at the same time. It feels like the sort of thing that might be possible but technically unfeasible given the amount of effort required. Personally I'd be curious to see how probable this is.
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    this Q&A has the (positive) answer except for the CRC part
    $endgroup$
    – SEJPM
    9 hours ago

















4












$begingroup$


I'm aware that individually, each has its weaknesses (especially CRC32), but is it feasible that a file could be created to falsely match all three?










share|improve this question









$endgroup$




migrated from superuser.com 9 hours ago


This question came from our site for computer enthusiasts and power users.


















  • $begingroup$
    I think it would be difficult to actively intend to get a simultaneous clash on all three given that they use different algorithms. Clashes are possible in each, sure, and you can engineer a clash in each if you are determined but I would have thought it would be difficult to get a clash in all three at the same time. It feels like the sort of thing that might be possible but technically unfeasible given the amount of effort required. Personally I'd be curious to see how probable this is.
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    this Q&A has the (positive) answer except for the CRC part
    $endgroup$
    – SEJPM
    9 hours ago













4












4








4


1



$begingroup$


I'm aware that individually, each has its weaknesses (especially CRC32), but is it feasible that a file could be created to falsely match all three?










share|improve this question









$endgroup$




I'm aware that individually, each has its weaknesses (especially CRC32), but is it feasible that a file could be created to falsely match all three?







checksum md5 crc sha-1






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 10 hours ago







Hiccup












migrated from superuser.com 9 hours ago


This question came from our site for computer enthusiasts and power users.











migrated from superuser.com 9 hours ago


This question came from our site for computer enthusiasts and power users.









migrated from superuser.com 9 hours ago


This question came from our site for computer enthusiasts and power users.













  • $begingroup$
    I think it would be difficult to actively intend to get a simultaneous clash on all three given that they use different algorithms. Clashes are possible in each, sure, and you can engineer a clash in each if you are determined but I would have thought it would be difficult to get a clash in all three at the same time. It feels like the sort of thing that might be possible but technically unfeasible given the amount of effort required. Personally I'd be curious to see how probable this is.
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    this Q&A has the (positive) answer except for the CRC part
    $endgroup$
    – SEJPM
    9 hours ago
















  • $begingroup$
    I think it would be difficult to actively intend to get a simultaneous clash on all three given that they use different algorithms. Clashes are possible in each, sure, and you can engineer a clash in each if you are determined but I would have thought it would be difficult to get a clash in all three at the same time. It feels like the sort of thing that might be possible but technically unfeasible given the amount of effort required. Personally I'd be curious to see how probable this is.
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    this Q&A has the (positive) answer except for the CRC part
    $endgroup$
    – SEJPM
    9 hours ago















$begingroup$
I think it would be difficult to actively intend to get a simultaneous clash on all three given that they use different algorithms. Clashes are possible in each, sure, and you can engineer a clash in each if you are determined but I would have thought it would be difficult to get a clash in all three at the same time. It feels like the sort of thing that might be possible but technically unfeasible given the amount of effort required. Personally I'd be curious to see how probable this is.
$endgroup$
– Mokubai
9 hours ago




$begingroup$
I think it would be difficult to actively intend to get a simultaneous clash on all three given that they use different algorithms. Clashes are possible in each, sure, and you can engineer a clash in each if you are determined but I would have thought it would be difficult to get a clash in all three at the same time. It feels like the sort of thing that might be possible but technically unfeasible given the amount of effort required. Personally I'd be curious to see how probable this is.
$endgroup$
– Mokubai
9 hours ago












$begingroup$
this Q&A has the (positive) answer except for the CRC part
$endgroup$
– SEJPM
9 hours ago




$begingroup$
this Q&A has the (positive) answer except for the CRC part
$endgroup$
– SEJPM
9 hours ago










1 Answer
1






active

oldest

votes


















5












$begingroup$

Finding a simultaneous collision for all three would take the effort of approximately $2^72$ SHA-1 compression function evaluations.



The overall idea would be to take the general $2^67$ idea found in the answer to How hard is it to generate a simultaneous MD5 and SHA1 collision? and perform the attack 33 successive times (generating 33 places in the hash image where we can take either $X_i$ or $Y_i$ without affecting either the MD5 or SHA-1 hash).



That'll give us a total of $2^33$ images with all the same MD5 and SHA-1 hash; there must be a pair of images with the same CRC-32 value as well, and so that solves the problem.



Whether $2^72$ operations is in the realm of feasibility is another question entirely...






share|improve this answer









$endgroup$














  • $begingroup$
    I was brought here by the curiosity of the question and I'm a bit hung up on the feasibility side. Yes it is technically possible but 2^72 is a number that my mind just spits back as "impossibly huge". Does this mean it is within the realms of a guy sitting in a basement with an old i3 box or is it all the computers in the world running until the eventual heat death of the universe?
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    @Mokubai: it's probably closer to 'if the NSA (or possibly Goggle or Amazon) decide to devote all their assets on this one problem, they could probably do it in a not-unreasonable amount of time...'.
    $endgroup$
    – poncho
    8 hours ago










  • $begingroup$
    Okay, so it's within the realms of possibility of nation-state actors, but probably beyond your average malware or script-kiddie. That is unless he has a pretty large botnet... Not unreasonable to achieve, but probably costs far more than it is ever going to worth unless the target is a) incredibly paranoid (to be using/checking all three hashes) and b) extremely high value. Thank you for indulging my curiosity :)
    $endgroup$
    – Mokubai
    8 hours ago






  • 1




    $begingroup$
    The Bitcoin network has a hash rate of $2^72$ hashes every three days. It's more than one guy in a basement but far less than heat death of the universe. It's also probably far less than what the NSA could manage.
    $endgroup$
    – djao
    6 hours ago






  • 1




    $begingroup$
    I was half expecting to see an answer of "Yeah, these two files."
    $endgroup$
    – Joshua
    2 hours ago













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1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









5












$begingroup$

Finding a simultaneous collision for all three would take the effort of approximately $2^72$ SHA-1 compression function evaluations.



The overall idea would be to take the general $2^67$ idea found in the answer to How hard is it to generate a simultaneous MD5 and SHA1 collision? and perform the attack 33 successive times (generating 33 places in the hash image where we can take either $X_i$ or $Y_i$ without affecting either the MD5 or SHA-1 hash).



That'll give us a total of $2^33$ images with all the same MD5 and SHA-1 hash; there must be a pair of images with the same CRC-32 value as well, and so that solves the problem.



Whether $2^72$ operations is in the realm of feasibility is another question entirely...






share|improve this answer









$endgroup$














  • $begingroup$
    I was brought here by the curiosity of the question and I'm a bit hung up on the feasibility side. Yes it is technically possible but 2^72 is a number that my mind just spits back as "impossibly huge". Does this mean it is within the realms of a guy sitting in a basement with an old i3 box or is it all the computers in the world running until the eventual heat death of the universe?
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    @Mokubai: it's probably closer to 'if the NSA (or possibly Goggle or Amazon) decide to devote all their assets on this one problem, they could probably do it in a not-unreasonable amount of time...'.
    $endgroup$
    – poncho
    8 hours ago










  • $begingroup$
    Okay, so it's within the realms of possibility of nation-state actors, but probably beyond your average malware or script-kiddie. That is unless he has a pretty large botnet... Not unreasonable to achieve, but probably costs far more than it is ever going to worth unless the target is a) incredibly paranoid (to be using/checking all three hashes) and b) extremely high value. Thank you for indulging my curiosity :)
    $endgroup$
    – Mokubai
    8 hours ago






  • 1




    $begingroup$
    The Bitcoin network has a hash rate of $2^72$ hashes every three days. It's more than one guy in a basement but far less than heat death of the universe. It's also probably far less than what the NSA could manage.
    $endgroup$
    – djao
    6 hours ago






  • 1




    $begingroup$
    I was half expecting to see an answer of "Yeah, these two files."
    $endgroup$
    – Joshua
    2 hours ago















5












$begingroup$

Finding a simultaneous collision for all three would take the effort of approximately $2^72$ SHA-1 compression function evaluations.



The overall idea would be to take the general $2^67$ idea found in the answer to How hard is it to generate a simultaneous MD5 and SHA1 collision? and perform the attack 33 successive times (generating 33 places in the hash image where we can take either $X_i$ or $Y_i$ without affecting either the MD5 or SHA-1 hash).



That'll give us a total of $2^33$ images with all the same MD5 and SHA-1 hash; there must be a pair of images with the same CRC-32 value as well, and so that solves the problem.



Whether $2^72$ operations is in the realm of feasibility is another question entirely...






share|improve this answer









$endgroup$














  • $begingroup$
    I was brought here by the curiosity of the question and I'm a bit hung up on the feasibility side. Yes it is technically possible but 2^72 is a number that my mind just spits back as "impossibly huge". Does this mean it is within the realms of a guy sitting in a basement with an old i3 box or is it all the computers in the world running until the eventual heat death of the universe?
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    @Mokubai: it's probably closer to 'if the NSA (or possibly Goggle or Amazon) decide to devote all their assets on this one problem, they could probably do it in a not-unreasonable amount of time...'.
    $endgroup$
    – poncho
    8 hours ago










  • $begingroup$
    Okay, so it's within the realms of possibility of nation-state actors, but probably beyond your average malware or script-kiddie. That is unless he has a pretty large botnet... Not unreasonable to achieve, but probably costs far more than it is ever going to worth unless the target is a) incredibly paranoid (to be using/checking all three hashes) and b) extremely high value. Thank you for indulging my curiosity :)
    $endgroup$
    – Mokubai
    8 hours ago






  • 1




    $begingroup$
    The Bitcoin network has a hash rate of $2^72$ hashes every three days. It's more than one guy in a basement but far less than heat death of the universe. It's also probably far less than what the NSA could manage.
    $endgroup$
    – djao
    6 hours ago






  • 1




    $begingroup$
    I was half expecting to see an answer of "Yeah, these two files."
    $endgroup$
    – Joshua
    2 hours ago













5












5








5





$begingroup$

Finding a simultaneous collision for all three would take the effort of approximately $2^72$ SHA-1 compression function evaluations.



The overall idea would be to take the general $2^67$ idea found in the answer to How hard is it to generate a simultaneous MD5 and SHA1 collision? and perform the attack 33 successive times (generating 33 places in the hash image where we can take either $X_i$ or $Y_i$ without affecting either the MD5 or SHA-1 hash).



That'll give us a total of $2^33$ images with all the same MD5 and SHA-1 hash; there must be a pair of images with the same CRC-32 value as well, and so that solves the problem.



Whether $2^72$ operations is in the realm of feasibility is another question entirely...






share|improve this answer









$endgroup$



Finding a simultaneous collision for all three would take the effort of approximately $2^72$ SHA-1 compression function evaluations.



The overall idea would be to take the general $2^67$ idea found in the answer to How hard is it to generate a simultaneous MD5 and SHA1 collision? and perform the attack 33 successive times (generating 33 places in the hash image where we can take either $X_i$ or $Y_i$ without affecting either the MD5 or SHA-1 hash).



That'll give us a total of $2^33$ images with all the same MD5 and SHA-1 hash; there must be a pair of images with the same CRC-32 value as well, and so that solves the problem.



Whether $2^72$ operations is in the realm of feasibility is another question entirely...







share|improve this answer












share|improve this answer



share|improve this answer










answered 9 hours ago









ponchoponcho

98.2k2 gold badges160 silver badges258 bronze badges




98.2k2 gold badges160 silver badges258 bronze badges














  • $begingroup$
    I was brought here by the curiosity of the question and I'm a bit hung up on the feasibility side. Yes it is technically possible but 2^72 is a number that my mind just spits back as "impossibly huge". Does this mean it is within the realms of a guy sitting in a basement with an old i3 box or is it all the computers in the world running until the eventual heat death of the universe?
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    @Mokubai: it's probably closer to 'if the NSA (or possibly Goggle or Amazon) decide to devote all their assets on this one problem, they could probably do it in a not-unreasonable amount of time...'.
    $endgroup$
    – poncho
    8 hours ago










  • $begingroup$
    Okay, so it's within the realms of possibility of nation-state actors, but probably beyond your average malware or script-kiddie. That is unless he has a pretty large botnet... Not unreasonable to achieve, but probably costs far more than it is ever going to worth unless the target is a) incredibly paranoid (to be using/checking all three hashes) and b) extremely high value. Thank you for indulging my curiosity :)
    $endgroup$
    – Mokubai
    8 hours ago






  • 1




    $begingroup$
    The Bitcoin network has a hash rate of $2^72$ hashes every three days. It's more than one guy in a basement but far less than heat death of the universe. It's also probably far less than what the NSA could manage.
    $endgroup$
    – djao
    6 hours ago






  • 1




    $begingroup$
    I was half expecting to see an answer of "Yeah, these two files."
    $endgroup$
    – Joshua
    2 hours ago
















  • $begingroup$
    I was brought here by the curiosity of the question and I'm a bit hung up on the feasibility side. Yes it is technically possible but 2^72 is a number that my mind just spits back as "impossibly huge". Does this mean it is within the realms of a guy sitting in a basement with an old i3 box or is it all the computers in the world running until the eventual heat death of the universe?
    $endgroup$
    – Mokubai
    9 hours ago










  • $begingroup$
    @Mokubai: it's probably closer to 'if the NSA (or possibly Goggle or Amazon) decide to devote all their assets on this one problem, they could probably do it in a not-unreasonable amount of time...'.
    $endgroup$
    – poncho
    8 hours ago










  • $begingroup$
    Okay, so it's within the realms of possibility of nation-state actors, but probably beyond your average malware or script-kiddie. That is unless he has a pretty large botnet... Not unreasonable to achieve, but probably costs far more than it is ever going to worth unless the target is a) incredibly paranoid (to be using/checking all three hashes) and b) extremely high value. Thank you for indulging my curiosity :)
    $endgroup$
    – Mokubai
    8 hours ago






  • 1




    $begingroup$
    The Bitcoin network has a hash rate of $2^72$ hashes every three days. It's more than one guy in a basement but far less than heat death of the universe. It's also probably far less than what the NSA could manage.
    $endgroup$
    – djao
    6 hours ago






  • 1




    $begingroup$
    I was half expecting to see an answer of "Yeah, these two files."
    $endgroup$
    – Joshua
    2 hours ago















$begingroup$
I was brought here by the curiosity of the question and I'm a bit hung up on the feasibility side. Yes it is technically possible but 2^72 is a number that my mind just spits back as "impossibly huge". Does this mean it is within the realms of a guy sitting in a basement with an old i3 box or is it all the computers in the world running until the eventual heat death of the universe?
$endgroup$
– Mokubai
9 hours ago




$begingroup$
I was brought here by the curiosity of the question and I'm a bit hung up on the feasibility side. Yes it is technically possible but 2^72 is a number that my mind just spits back as "impossibly huge". Does this mean it is within the realms of a guy sitting in a basement with an old i3 box or is it all the computers in the world running until the eventual heat death of the universe?
$endgroup$
– Mokubai
9 hours ago












$begingroup$
@Mokubai: it's probably closer to 'if the NSA (or possibly Goggle or Amazon) decide to devote all their assets on this one problem, they could probably do it in a not-unreasonable amount of time...'.
$endgroup$
– poncho
8 hours ago




$begingroup$
@Mokubai: it's probably closer to 'if the NSA (or possibly Goggle or Amazon) decide to devote all their assets on this one problem, they could probably do it in a not-unreasonable amount of time...'.
$endgroup$
– poncho
8 hours ago












$begingroup$
Okay, so it's within the realms of possibility of nation-state actors, but probably beyond your average malware or script-kiddie. That is unless he has a pretty large botnet... Not unreasonable to achieve, but probably costs far more than it is ever going to worth unless the target is a) incredibly paranoid (to be using/checking all three hashes) and b) extremely high value. Thank you for indulging my curiosity :)
$endgroup$
– Mokubai
8 hours ago




$begingroup$
Okay, so it's within the realms of possibility of nation-state actors, but probably beyond your average malware or script-kiddie. That is unless he has a pretty large botnet... Not unreasonable to achieve, but probably costs far more than it is ever going to worth unless the target is a) incredibly paranoid (to be using/checking all three hashes) and b) extremely high value. Thank you for indulging my curiosity :)
$endgroup$
– Mokubai
8 hours ago




1




1




$begingroup$
The Bitcoin network has a hash rate of $2^72$ hashes every three days. It's more than one guy in a basement but far less than heat death of the universe. It's also probably far less than what the NSA could manage.
$endgroup$
– djao
6 hours ago




$begingroup$
The Bitcoin network has a hash rate of $2^72$ hashes every three days. It's more than one guy in a basement but far less than heat death of the universe. It's also probably far less than what the NSA could manage.
$endgroup$
– djao
6 hours ago




1




1




$begingroup$
I was half expecting to see an answer of "Yeah, these two files."
$endgroup$
– Joshua
2 hours ago




$begingroup$
I was half expecting to see an answer of "Yeah, these two files."
$endgroup$
– Joshua
2 hours ago

















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