CN1694394A - Deciphering method for file password - Google Patents
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- CN1694394A CN1694394A CN 200510025068 CN200510025068A CN1694394A CN 1694394 A CN1694394 A CN 1694394A CN 200510025068 CN200510025068 CN 200510025068 CN 200510025068 A CN200510025068 A CN 200510025068A CN 1694394 A CN1694394 A CN 1694394A
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Abstract
This invention relates to a hack method to a document password, first of all, which judges if the a word documentation, zip documentation or an image document have been ciphered already, then picks up key information used in the period of hacking the word password, then the back program generates possible password automatically and substitutes it to the test to present hacked password or failure information finally, which can realize high speed hack to word, ZIP and image ciphered passwords without knowing the password or part information of the password.
Description
Technical field
What the present invention relates to is a kind of technology that cracks automatically of file encryption password, specifically is a kind of crack method of file password.Belong to network information technology field.
Background technology
Along with the develop rapidly of computer, the communication technology, information security has become a major issue in current information epoch.At information security field, the information security service is an important service consultation class industry, it relates to numerous associated safety technological service categories such as security incident emergency response, damaged data recovery, code breaking, network security safeguards system structure, risk assessment, security strategy formulation, has obtained social many-sided approval.
It is an important service that belongs in the information security service field that encrypt file cracks.In actual environment, application program occurs through regular meeting and at will do not checked for the data file of protecting its particular type a class password code gives encipherment protection to file phenomenon is set.If this class file user do not know or lost the file encryption password, then it is cracked sometimes and be very important.Exemplary as, a user encrypts his vital document, but for a certain reason, it has forgotten password code, just needs to use the technology that crack in this case.And for example, for state security department etc., under some necessary situation, it may need the encrypt file of some unknown passwords is cracked.Currently used typical case cracks mode has the Brute Force and the dictionary of Brute Force (exhaustive cracking arranged into), band mask to crack three kinds of modes.Brute Force is meant attempts all possible password combination in the scope of appointment, it cracks the general needs cost plenty of time; The Brute Force of band mask is meant and is used in combination known cryptopart and Brute Force password unknown portions under the situation of knowing partial password in advance, it need know partial password in advance, if known to partial password less, also need usually to spend the more time of cracking; Dictionary cracks and is meant and uses the word be stored in the special dictionary file to crack trial, and it is reasonable that it needs the dictionary structure to improve as far as possible, otherwise the possibility that cracks failure is very big.More than these three kinds of methods all be earlier with various possible password substitutions, judge by some key message whether this password is accurate password then.In the encryption method of not knowing certain document or in the cryptographic algorithm that the document adopts is under the situation of non-reversible algorithm, and the method for this checking by substitution almost is unique selection.People use these modes to carry out craft sometimes and crack, unless but the cracker knows more relevant information in advance, otherwise will need a large amount of workloads usually.For this reason, under situation with good conditionsi, it also is the important tool that people use that encrypt file cracks automatically.
Have the image file of magnanimity on the Internet, mainly contain several forms of JPG, BMP and GIF.When we want to protect some image information not obtained by other people; tend to this image is carried out password encryption; have only encipherer oneself like this or know that the talent of password can check complete original image, and the resulting just one group of rambling data of other people.But, in some cases, when having forgotten that the encipherer password or network supervision department will examine some image information, we may need by manual or automatically method crack the password of an encrypted image.But, so far, aspect image encryption, also there is not any algorithm to be accepted extensively by everybody, different encryption softwares or the different cryptographic algorithm that the people adopted are far from each other, this just makes a kind of image crack and can only work at a kind of or limited several image encryption softwares that its scope of application is relatively limited.
Can be used for the software of encrypted image can be divided into special image encryption software and universal file encryption software according to function, and the former is such as Cryptapix, and Privatepix or the like, the latter be such as SilverKey, Inter-scopeBlackBox or the like.Can be divided into block encryption type software or sequential encryption software according to cryptographic algorithm, the former is such as the Cryptapix of the SliverKey that adopts aes algorithm and employing 56bitDES or blowfish algorithm, and the latter is such as the cryptbmp and the cryptjpeg of the exploitation of efg2 computer laboratory.
MsWord is current the most popular word processor, and the password encryption protection algorithm that the word software of earlier version is provided is directly data and password to be carried out XOR, and fail safe is very low.From MsWord2000, this software begins the encryption method that adopts MD5 and RC4 algorithm to combine, makes the fail safe of word document significantly promote.Nowadays various encryption Word documents are seen everywhere on network, therefore, develop a kind of password cracking software at MsWord and seem that ten minutes is necessary.At present, there have been many companies to develop password cracking software at MsWord, such as Advanced Word 2000 Password Recovery or the like, these softwares have all adopted Brute Force bar none, and dictionary cracks and cracks algorithm for these three kinds with the Brute Force of mask.Yet the core algorithm that now online common various Word crack is all maintained secrecy, if having leak or hidden door in certain software, in a single day the user has used this software so, might cause the leakage of important information.In view of this, we study for the automatic password cracking of encrypting the word document.
ZIP is current the most popular document compressed software, and various encryption ZIP documents are seen everywhere on network, therefore, develops a kind of password cracking software at the ZIP document and seems that ten minutes is necessary.At present, there have been many companies to develop password cracking software at the ZIP document, as: ZIP Passwordfinder.The core algorithm that online equally, now common various ZIP crack is also all maintained secrecy.
Because the particularity of image encryption, the software that cracks the encrypted image password is seldom arranged now on the net, so we have designed at the password cracking instrument by the image file of " star of encryption " software cryptography, in view of the use at home of " star of encryption " software is comparatively extensive, so this money cracks or no small use prospect is arranged.Though the password cracking software at word document and ZIP document is many, the source code and the core algorithm of these softwares are all maintained secrecy, and are unfavorable for that we carry out function expansion and optimization.In addition, though the word password cracking software of most of main flow such as Advanced Word 2000 Password Recovery speed are fast, what the kernel program of this software adopted is single-threaded mode.Therefore when cracking complicated password because the surge of operation time, resource for computer system for a long time the program of being cracked monopolize and can't normal response other request.If this kind situation occurs on the not strong computer of some disposal ability, problems such as memory overflow (because system does not have enough responding abilities to reclaim resource) and deadlock just take place probably.In addition, the ability of present most ZIP password cracking program test passwords is all about 200,000 of per seconds, and for cracking figure place height, the complicated password of combination, this speed is obviously not enough.
Summary of the invention
The objective of the invention is to overcome deficiency of the prior art, a kind of crack method of file password is provided, make it under the situation of complete unknown password or known password partial information, realize that the high speed of word, ZIP and image encryption password cracks.
The present invention is achieved by the following technical solutions, the present invention is at first for a word document, ZIP document or an image file, judge whether it is encrypted, its less important extraction cracks the key message that must use in the word password process, crack the information of program then according to the relevant password of user's input, automatically generate password and checking by substitution, provide the password that cracks out at last or crack the information of failure.
Describedly to judge whether it is encrypted, be meant: judge according to some special flag bit or flag information whether certain file is encrypted, each word document is made up of various streams and FIB (fileinformation block), in FIB, stored the state information of the document, the 1st of the 11st byte of FIB is exactly whether characterize this document be the information bit of encrypted document, after a document is encrypted, Word software can be set to 1 to this flag bit from 0, therefore, by extracting this flag bit, just can judge the word document of user's input and whether encrypt.
As following table:
| ?dec | ?hex | ?name | ?type | size | ?bitfield ?mask | ?comments |
| ?0-9 | ?0x0000 | ?other?information?of?this ?document | ||||
| ?10 | ?0x000a | ?fdot | ?ushort | ：1 | ?0x0001 | ?set?if?this?document?is?a?template |
| ?fglsy | ?ushort | ：1 | ?0x0002 | ?set?if?this?document?is?a?glossary | ||
| ?fcomplex | ?ushort | ：1 | ?0x0004 | ?when?1，file?is?in?complex， ?fast-saved?format. | ||
| ?fhaspic | ?ushort | ：1 | ?0x0008 | ?set?if?file?contains?1?or?more ?pictures | ||
| ?cquicksaves | ?ushort | ：4 | ?0x00f0 | ?count?of?times?file?was?quicksaved | ||
| ?fencrypted | ?ushort | ：1 | ?0x0100 | ?set?if?file?is?encrypted |
The ZIP document generally comprises local file head, file data district, central directory and tail of file structure.Wherein whether Bit 0 expression ZIP document is encrypted in the conventional sign of local file head, after a document was encrypted, ZIP software can be set to 1 to this flag bit from 0, therefore, by extracting this flag bit, whether we just can judge the ZIP document of user's input and encrypt.ZIP file structure such as following table:
The local file header structure:
| Flag bit (504b0304) | The decompress(ion) version | Conventional sign | Compression method | Modification time | Revise the date | ?CRC32 | |
| ???CRC32 | Size after the File Compress | Size before the File Compress | Filename is long | The expansion head of district | |||
| Filename (random length) expansion area (random length) | |||||||
The central directory structure:
| Flag bit (504b0102) | Compressed version | The decompress(ion) version | Conventional sign | Compression method | Modification time | Revise the date | |
| ??????CRC32 | Size after the File Compress | Size before the File Compress | Filename is long | The expansion head of district | |||
| Note length | Disk number | File attribute | The external file attribute | The local file relativity shift | |||
| Filename (random length) expansion area (random length) file note (random length) | |||||||
Zip tail of file structure:
| Flag bit (504b0506) | Disk number | The beginning disk | The catalogue number | The file number | Central directory district size |
| The skew of central directory district | Note is long | Zip file note (random length) | |||
For the image file of the star software cryptography of adopting encryption, its 3000 bytes of taking the lead all are the software relevant informations of fixing, so by this 3000 byte of check, just can judge whether this document had been encrypted by the star of encryption.
Described will the extraction cracked the key message that must use in the word password process, is meant: through after the judgement of previous step, cracking the previous work of word password, is exactly to extract some data relevant with password authentication or data blocks from encrypt file.
When cracking the word password, need at first to extract since the data of continuous three 16 byte longs of the 5th byte from the form stream (tableflow) of document, they are respectively document id (docid), seed (salt), the hashed value of seed (hashedsalt).When cracking ZIP document password, need read 12 bytes and encrypt the highest individual character of file CRC in head and the local file head/or byte.When cracking the password of image file, then need to read 3000 bytes of top of file and 3000 byte information of afterbody.
The described information that cracks program according to the relevant password of user's input, be meant: the password relevant information according to user's input produces possible password to be detected, and the substitution password authentication is partly verified its correctness.
Here the password relevant information of being said comprises the possible length of password, the setting of character set, and the setting of password mask.The program of cracking is exactly to come the various possible passwords of exhaustive generation according to these information, concrete generating algorithm is as follows: at first the character set that the user is selected is combined into a Charset, an integer array α [N] (N equals the length of current password to be measured) is set then, its i bit value has just been represented the offset address of i position in character set Charset of current password character string password, i.e. password[i]=Charset[α [i]].Like this, as long as the content of α [N] lining one becomes, the content of password also can change thereupon.
This process mainly is made up of two circulations, the variation of outer loop control password length N, interior loop then under the certain situation of password length, exhaustive various may, wherein Len is the length of the character set set of user.And the renewal each time of α [N] similarly is to have done an add operation, implements very convenient.
The exhaust algorithm of another is exactly the exhaustive of band mask, it is similar with above-mentioned exhaust algorithm, just the user has known the partial content of correct password, program is then gone the remaining part of exhaustive password, this has been equivalent to reduce exhaustive figure place, so the required time of password cracking can shorten greatly.Because the position of mask in password of user's input is also uncertain, specifically:
Step1. mask (mask) chain is obtained new password ' to the password afterbody.
Step2. mask moves forward one, is positioned at one digit number before the mask originally according to moving on after the mask that.
Step3. repeat 2 operation, be positioned at password ' foremost up to mask.
Described automatic generation password and checking by substitution are meant: password to be detected will carry out verifying correctness to it after generating, and concrete check algorithm is different according to the difference of file encrypting method.For the word password cracking, this process more complicated, MD5 and RC4 are two kinds of most important in word document decrypting process algorithms, the MD5 hash function is mainly used to generate one to carry out five hash computings and obtains a hashed value password to be detected and docid, and next the RC4 algorithm can carry out certain conversion with preceding 5 bytes of this hashed value and obtains the decruption key of oneself.After obtaining decruption key, the RC4 algorithm is used this key and is removed decryption information hashedsalt and salt, after the deciphering, calculate the MD5 hashed value of salt, if this hashed value is identical with hashedsalt, then the password of this check is exactly correct password, if different, continues checking with regard to the next password of substitution so.
For the password cracking of ZIP document, need at first decipher 12 bytes and encrypt head, relatively encrypt then the highest individual character in the head/or byte and local file head in the highest individual character/or byte of CRC, if the version before the identical then PKZIP2.0 version uses 2 byte crc checks, 2.0 editions later versions use 1 byte crc check.The process that reads and decipher 12 bytes encryption head is as follows:
loop?for?i<-0?to?11
c<-buffer(i)^decrypt_byte()
update_keys(c)
buffer(i)<-c
end?loop
Wherein decrypt_byte () function definition is as:
unsigned?char?decrypt_byte()
local?unsigned?short?temp
temp<-key(2)|2
decrypt_byte<-(temp*(temp^1))>>8
end?decrypt_byte
Compare, the password authentication process of image file is just much simple, and this is main because the algorithm that the star software of encryption is adopted is fairly simple.If go to do XOR with 16 byte data of file cipher text piece with 16 byte data of afterbody Plaintext block, then can obtain 16 byte MD5 hashed values of encrypted ones, Here it is, and we verify the foundation of password correctness to be detected.Below work be exactly calculate 16 byte hashed values of each password to be detected and judge it whether with correct Hash value matches.
The described information that provides the password that cracks out at last or crack failure is meant: at the exhaustive crack method of word, ZIP and image file, dictionary cracks and cracks with mask all is the improvement that cracks for exhaustive.Dictionary crack exactly in whole possible password space, select a high probability the subspace as a dictionary, do like this and can get rid of the little password of a lot of possibilities.At people the custom of password is set, the present invention has designed the telephone number dictionary, birthday dictionary, the password dictionary of the contour performance of word dictionary.The prerequisite that mask cracks be the user known the part the password content, need exhaustive figure place to reduce like this.Adopt mask and dictionary to crack the speed that all can accelerate password cracking far and away greatly.
The present invention has the very high speed that cracks and cracks efficient, the fluctuation about 148000 (individual/second) of Word password cracking speed, this speed has been higher than most professional Word password cracking software, this suffices to show that the present invention has higher availability, the fluctuation about 521000 (individual/second) of the password cracking speed of ZIP document of the present invention, this speed has been higher than most professional ZIP password cracking software, as: ZIP password finder average speed is 202300 (individual/second).The fluctuation about 357000 (individual/second) of the password cracking speed of the present invention's image document.
Embodiment
Developed word document, ZIP document and image file password based on the present invention and cracked at a high speed, the present invention mainly comprises the key message extraction module, and institute might password generation module and password verification of correctness module.At first, according to corresponding the cracking of form startup of file, generally speaking, no matter word, ZIP or image file, after encryption, its suffix name is constant; Afterwards, from file, extract special flag information earlier and judge whether this document is encrypted, if, extract some again and crack the key message that to use in the process through encrypting; Then, the request user relevant information of entering password, promptly the minimum and maximum length of password is selected possible character set, and mask (optional) is set, and dictionary (optional) etc. is set.Next, the program of cracking can be come exhaustive generation or directly read (at the dictionary crack method) possible password according to those information of user input, and the password that each is possible is delivered to password verification of correctness module as password to be detected and verified; At last, if found correct password, Automatic Program stops so, exports this password.If do not find, the output information specific to the present invention, is pointed out parameters such as user's resetting password length, character set exactly.
Developed respectively at encrypting Word document based on the present invention, three high speed passwords of ZIP document and image literary composition crack, and each software comprises all that key message extracts, possible password generates, these three main modular of password verification of correctness.Generally speaking, be constant through the suffix name of the file of password encryption, therefore, when implementing to crack, we are according to waiting that the suffix name that cracks file selects corresponding software.Be the specific implementation method that example is specifically introduced password cracking with cracking of ZIP document below.At first, the user starts ZIP document password cracking software, and click file selector button is chosen and treated Cracking Doc, and after choosing, background program can extract some specific information positions from the ZIP document automatically and judge whether the document is encrypted document.Afterwards, the user cracks relevant information according to the crack method setting that oneself will take, and is as shown in the table:
| Crack method | The relevant information that needs setting |
| The method of exhaustion | The minimum and maximum length of password, the password character set |
| The method of exhaustion of band mask | The minimum and maximum length of password, password character set, mask character or character string |
| Dictionary method | The password dictionary |
After all information setting are appropriate, just password cracking can have been begun.Next, crack program and can generate a password to be tested earlier automatically.If the algorithm that cracks that the user takes is (band mask) method of exhaustion, this password to be tested is that program is brought password character set, password length, the mask character (string) of user's input into the password generating algorithm and calculated and get so; If what the user taked is the dictionary crack method, this password directly reads from the password dictionary so.Then, password to be tested will be delivered to the password inspection module and carry out accuracy verification.If this checking is passed through, show that then this password is exactly correct password, program will provide information and inform that the user cracks success, and this correct password of output.If do not pass through, then read in next password to be tested.But do not find correct password yet if all passwords to be tested have all inspected, program provides the information that cracks failure, specific to this software, points out parameters such as user's resetting password length, character set exactly.
The specific embodiments and the such scheme of Word document and image file password cracking are basic identical, are just judging that whether encrypted file when checking password correctness, the specific algorithm difference that is adopted.
Claims (8)
1, a kind of crack method of file password, it is characterized in that, at first for a word document, ZIP document or an image file, judge whether it is encrypted, its less important extraction cracks the key message that must use in the word password process, crack the information of program then, generate possible password and checking by substitution automatically, provide the password that cracks out at last or crack the information of failure according to the relevant password of user input.
2, the crack method of file password according to claim 1, it is characterized in that, describedly to judge whether it is encrypted, be meant: judge according to some special flag bit or flag information whether certain file is encrypted, each word document is made up of various streams and FIB, in FIB, stored the state information of the document, the 1st of the 11st byte of FIB is exactly whether characterize this document be the information bit of encrypted document, after a document is encrypted, Word software can be set to 1 to this flag bit from 0, therefore, by extracting this flag bit, just can judge the word document of user's input and whether encrypt.
3, the crack method of file password according to claim 1, it is characterized in that, described will the extraction cracked the key message that must use in the word password process, be meant: through after the judgement of previous step, crack the previous work of word password, be exactly from encrypt file, to extract some data relevant or data blocks with password authentication, when cracking the word password, need at first from the form stream of document, to extract since the data of continuous three 16 byte longs of the 5th byte, when cracking the password of image file, then need to read 3000 bytes of top of file and 3000 byte information of afterbody.
4, the crack method of file password according to claim 1, it is characterized in that, the described information that cracks program according to the relevant password of user's input, be meant: the password relevant information according to user's input produces possible password to be detected, and the substitution password authentication is partly verified its correctness, described cracking, its program is come the various possible passwords of exhaustive generation according to these information, concrete generation exhaust algorithm is as follows: at first the character set that the user is selected is combined into a Charset, an integer array a[N is set then] (N equals the length of current password to be measured), its i bit value has just been represented the offset address of i position in character set Charset of current password character string password, be password[i]=Charset[a[i]], as long as a[N] content one of lining becomes, the content of password also can change thereupon, this process is made up of two circulations, the variation of outer loop control password length N, interior loop is then under the certain situation of password length, exhaustive various may, wherein Len is the length of the character set set of user.
5, the crack method of file password according to claim 4, it is characterized in that, described exhaust algorithm, perhaps exhaustive with mask, it and above-mentioned exhaust algorithm are similar, just the user has known the partial content of correct password, program is then gone the remaining part of exhaustive password, and this has been equivalent to reduce exhaustive figure place, so the required time of password cracking can shorten greatly, because the position of mask in password of user's input is also uncertain, adds the 3rd and recirculate.
6, the crack method of file password according to claim 1, it is characterized in that, described automatic generation password and checking by substitution, be meant: after password to be detected generates, it is carried out verifying correctness, concrete check algorithm is different according to the difference of file encrypting method: for the word password cracking, MD5 and RC4 are two kinds of most important in word document decrypting process algorithms, the MD5 hash function is mainly used to generate one to carry out five hash computings and obtains a hashed value password to be detected and docid, the RC4 algorithm can carry out certain conversion with preceding 5 bytes of this hashed value and obtain the decruption key of oneself, after obtaining decruption key, the RC4 algorithm is used this key and is removed decryption information hashedsalt and salt, after the deciphering, calculate the MD5 hashed value of salt, if this hashed value is identical with hashedsalt, then the password of this check is exactly correct password, if different, continue checking with regard to the next password of substitution so.
7, the crack method of file password according to claim 1, it is characterized in that, the described information that provides the password that cracks out at last or crack failure, be meant: at the exhaustive crack method of word, ZIP and image file, dictionary cracks and cracks with mask all is the improvement that cracks for exhaustive, and dictionary cracks exactly and select the subspace of a high probability as a dictionary in whole possible password space.
8, the crack method of file password according to claim 7, it is characterized in that, described ZIP document, to its password cracking, need at first decipher 12 bytes and encrypt head, relatively encrypt then the highest individual character in the head/or byte and local file head in the highest individual character/or byte of CRC, if the version before the identical then PKZIP2.0 version uses 2 byte crc checks, 2.0 editions later versions use 1 byte crc check.
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102750495A (en) * | 2012-06-07 | 2012-10-24 | 北京锐安科技有限公司 | System for cracking and restoring iPhone encrypted backup files |
| CN102983967A (en) * | 2012-12-06 | 2013-03-20 | 厦门市美亚柏科信息股份有限公司 | Quick traversal algorithm and device for complicated password |
| CN104021320A (en) * | 2014-06-20 | 2014-09-03 | 福建天晴数码有限公司 | Method, device and system for protecting copyrights of APK files |
| CN105069334A (en) * | 2015-08-24 | 2015-11-18 | 上海数据分析与处理技术研究所 | Character range redefinition based password recovery method |
| CN105391716A (en) * | 2015-11-13 | 2016-03-09 | 上海斐讯数据通信技术有限公司 | Method and system for identifying encryption algorithm |
| CN108616512A (en) * | 2018-04-04 | 2018-10-02 | 广州慧睿思通信息科技有限公司 | A kind of improved PPT2003 files deciphering method and device |
| CN109344633A (en) * | 2018-09-28 | 2019-02-15 | 山东超越数控电子股份有限公司 | A kind of software decryption method based on mixed logic processor platform |
| CN110727950A (en) * | 2019-09-29 | 2020-01-24 | 无锡京和信息技术有限公司 | Distributed cooperative computing system and cooperative processing method |
| CN111783077A (en) * | 2020-06-15 | 2020-10-16 | 中国电子科技集团公司第三十研究所 | TrueCrypt encryption software password recovery method, encrypted data evidence obtaining system and storage medium |
| CN112487147A (en) * | 2020-12-02 | 2021-03-12 | 中国电子科技集团公司第三十研究所 | Automatic matching method, system, computer program and storage medium for password cracking algorithm |
| CN112861113A (en) * | 2021-01-08 | 2021-05-28 | 复旦大学 | Password guessing method of parameterized hybrid model |
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- 2005-04-14 CN CN 200510025068 patent/CN1694394A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102750495A (en) * | 2012-06-07 | 2012-10-24 | 北京锐安科技有限公司 | System for cracking and restoring iPhone encrypted backup files |
| CN102983967A (en) * | 2012-12-06 | 2013-03-20 | 厦门市美亚柏科信息股份有限公司 | Quick traversal algorithm and device for complicated password |
| CN102983967B (en) * | 2012-12-06 | 2015-09-02 | 厦门市美亚柏科信息股份有限公司 | The complicated quick ergodic algorithm of password and device |
| CN104021320A (en) * | 2014-06-20 | 2014-09-03 | 福建天晴数码有限公司 | Method, device and system for protecting copyrights of APK files |
| CN105069334A (en) * | 2015-08-24 | 2015-11-18 | 上海数据分析与处理技术研究所 | Character range redefinition based password recovery method |
| CN105391716B (en) * | 2015-11-13 | 2018-06-19 | 上海斐讯数据通信技术有限公司 | A kind of method and system for identifying Encryption Algorithm |
| CN105391716A (en) * | 2015-11-13 | 2016-03-09 | 上海斐讯数据通信技术有限公司 | Method and system for identifying encryption algorithm |
| CN108616512A (en) * | 2018-04-04 | 2018-10-02 | 广州慧睿思通信息科技有限公司 | A kind of improved PPT2003 files deciphering method and device |
| CN109344633A (en) * | 2018-09-28 | 2019-02-15 | 山东超越数控电子股份有限公司 | A kind of software decryption method based on mixed logic processor platform |
| CN110727950A (en) * | 2019-09-29 | 2020-01-24 | 无锡京和信息技术有限公司 | Distributed cooperative computing system and cooperative processing method |
| CN111783077A (en) * | 2020-06-15 | 2020-10-16 | 中国电子科技集团公司第三十研究所 | TrueCrypt encryption software password recovery method, encrypted data evidence obtaining system and storage medium |
| CN112487147A (en) * | 2020-12-02 | 2021-03-12 | 中国电子科技集团公司第三十研究所 | Automatic matching method, system, computer program and storage medium for password cracking algorithm |
| CN112861113A (en) * | 2021-01-08 | 2021-05-28 | 复旦大学 | Password guessing method of parameterized hybrid model |
| CN112861113B (en) * | 2021-01-08 | 2022-05-20 | 复旦大学 | Password guessing method of parameterized mixed model |
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