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host data and covertly broadcasts it. This makes it available to everyone, noticeable by no one (except the attacker), and only decipherable by the attacker. An attacker caught installing the cryptotrojan claims to be a virus victim. An attacker observed receiving the covert asymmetric broadcast is one of the thousands, if not millions of receivers, and exhibits no identifying information whatsoever. The cryptovirology attack achieves "end-to-end deniability." It is a covert asymmetric broadcast of the victim's data. Cryptovirology also encompasses the use of
681:. For example, the tremor virus used polymorphism as a defensive technique in an attempt to avoid detection by anti-virus software. Though cryptography does assist in such cases to enhance the longevity of a virus, the capabilities of cryptography are not used in the payload. The One-half virus was amongst the first viruses known to have encrypted affected files.
622:(PIR) to allow cryptoviruses to search for and steal host data without revealing the data searched for even when the cryptotrojan is under constant surveillance. By definition, such a cryptovirus carries within its own coding sequence the query of the attacker and the necessary PIR logic to apply the query to host systems.
548:, and security to users. Cryptovirology employs a twist on cryptography, showing that it can also be used offensively. It can be used to mount extortion based attacks that cause loss of access to information, loss of confidentiality, and information leakage, tasks which cryptography typically prevents.
559:
analyst sees regarding malware and what the attacker sees. The antivirus analyst sees a public key contained in the malware, whereas the attacker sees the public key contained in the malware as well as the corresponding private key (outside the malware) since the attacker created the key pair for the
617:
Covert information leakage attacks carried out by cryptoviruses, cryptotrojans, and cryptoworms that, by definition, contain and use the public key of the attacker is a major theme in cryptovirology. In "deniable password snatching," a cryptovirus installs a cryptotrojan that asymmetrically encrypts
613:
and that, although security professionals and developers have been testing and implementing kleptographic attacks since 1996, "you would be hard-pressed to find one in actual use until now." Due to public outcry about this cryptovirology attack, NIST rescinded the EC-DRBG algorithm from the NIST SP
608:
random bit generator has an asymmetric backdoor in it. The EC-DRBG algorithm utilizes the discrete-log kleptogram from kleptography, which by definition makes the EC-DRBG a cryptotrojan. Like ransomware, the EC-DRBG cryptotrojan contains and uses the attacker's public key to attack the host system.
638:
the victim's files. The malware prompts the user to send the asymmetric ciphertext to the attacker who will decipher it and return the symmetric decryption key it contains for a fee. The victim needs the symmetric key to decrypt the encrypted files if there is no way to recover the original files
663:
that is not permitted under HIPAA, the rationale being that an adversary has taken control of the information. Sensitive data might never leave the victim organization, but the break-in may have allowed data to be sent out undetected. California enacted a law that defines the introduction of
703:
and encrypts files with many different extensions. It instructs the owner of the machine to email a given mail ID if the owner desires the decryptor. If contacted by email, the user will be asked to pay a certain amount as ransom in return for the decryptor.
634:, at the time called "cryptoviral extortion" and it was presented at the 1996 IEEE Security & Privacy conference. In this attack, a cryptovirus, cryptoworm, or cryptotrojan contains the public key of the attacker and
689:
An example of a virus that informs the owner of the infected machine to pay a ransom is the virus nicknamed Tro_Ransom.A. This virus asks the owner of the infected machine to send $ 10.99 to a given account through
659:. The fact sheet states that when electronic protected health information is encrypted by ransomware, a breach has occurred, and the attack therefore constitutes a
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652:
848:
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The cryptographer Ari Juels indicated that NSA effectively orchestrated a kleptographic attack on users of the Dual EC DRBG pseudorandom number generation
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826:
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941:
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Apart from cryptoviral extortion, there are other potential uses of cryptoviruses, such as deniable password snatching, cryptocounters,
677:
While viruses in the wild have used cryptography in the past, the only purpose of such usage of cryptography was to avoid detection by
512:
1140:
592:) that can be used only by the attacker, even after it is found. This contrasts with the traditional backdoor that is symmetric,
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algorithms, key exchanges, pseudorandom number generators, encryption algorithms, and other cryptographic algorithms. The NIST
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639:(e.g., from backups). The 1996 IEEE paper predicted that cryptoviral extortion attackers would one day demand
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651:. In 2016, cryptovirology attacks on healthcare providers reached epidemic levels, prompting the U.S.
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600:, a subfield of cryptovirology, is the study of asymmetric backdoors in key generation algorithms,
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544:. Traditionally, cryptography and its applications are defensive in nature, and provide privacy,
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ransomware into a computer system with the intent of extortion as being against the law.
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732:, and in secure communication between different instances of a distributed cryptovirus.
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The first cryptovirology attack and discussion of the concept was by Adam L. Young and
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849:"NIST Removes Cryptography Algorithm from Random Number Generator Recommendations"
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58:
27:
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975:
823:"NSA Efforts to Evade Encryption Technology Damaged U.S. Cryptography Standard"
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545:
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260:
190:
71:
1074:
765:
1184:
1061:
Young, Adam L. (2006). "Cryptoviral extortion using
Microsoft's Crypto API".
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even existed. Many years later, the media relabeled cryptoviral extortion as
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state, and the victim's data. Examples of such covert attacks are asymmetric
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is a classic cryptovirus. This virus partially uses a version of 660-bit
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766:"Cryptovirology: Extortion-based security threats and countermeasures"
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operations on the victim's computer that only the attacker can undo.
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347:
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1101:"Cryptovirology Labs – Site maintained by Adam Young and Moti Yung"
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The field encompasses covert malware attacks in which the attacker
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steals private information such as symmetric keys, private keys,
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332:
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110:
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It has been demonstrated that using just 8 different calls to
1113:"Cryptography and cryptovirology articles – Computer viruses"
723:
656:
720:(CAPI), a cryptovirus can satisfy all its encryption needs.
1153:"A student report entitled 'Superworms and Cryptovirology'"
1006:"Sophos Security Labs: Real-Time Malware Threat Prevention"
1039:
770:
Proceedings 1996 IEEE Symposium on
Security and Privacy
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874:
560:
attack. The public key allows the malware to perform
1166:"Next Virus Generation: an Overview (cryptoviruses)"
965:SB-1137 that amends Section 523 of the Penal Code.
871:
555:can be used to break the symmetry between what an
1163:
880:
820:
1182:
883:Malicious Cryptography: Exposing Cryptovirology
841:
1129:"Cryzip Trojan Encrypts Files, Demands Ransom"
853:National Institute of Standards and Technology
814:
763:
1063:International Journal of Information Security
551:The field was born with the observation that
506:
923:
1141:"Can a virus lead an enterprise to court?"
724:Other uses of cryptography-enabled malware
513:
499:
976:"Tremor Description | F-Secure Labs"
905:
655:to issue a Fact Sheet on Ransomware and
584:. An asymmetric backdoor is a backdoor (
821:Larry Greenemeier (18 September 2013).
653:Department of Health and Human Services
1183:
1060:
909:Cryptovirology and malicious software
899:
684:
759:
757:
859:from the original on 29 August 2016
829:from the original on 18 August 2016
802:from the original on 8 October 2022
596:, anyone that finds it can use it.
233:forensics-focused operating systems
13:
947:from the original on 13 April 2018
931:"FACT SHEET: Ransomware and HIPAA"
14:
1207:
1093:
986:from the original on 24 June 2021
919:, department of computer science.
754:
16:Securing and encrypting virology
1054:
1024:
672:
54:Hacking of consumer electronics
998:
968:
959:
1:
917:University of Eastern Finland
764:Young, A.; Moti Yung (1996).
747:
730:private information retrieval
620:private information retrieval
153:Chaos Communication Congress
7:
735:
667:
567:
10:
1212:
915:(Master's thesis thesis).
881:A. Young, M. Yung (2004).
778:10.1109/SECPRI.1996.502676
625:
465:2600: The Hacker Quarterly
203:List of computer criminals
1075:10.1007/s10207-006-0082-7
906:Korsakov, Alexey (2014).
383:Cloud computing security
1164:Angelo P. E. Rosiello.
825:. Scientific American.
707:
553:public-key cryptography
528:refers to the study of
163:Hackers on Planet Earth
418:Homebrew Computer Club
1107:on 18 September 2020.
697:Virus.Win32.Gpcode.ag
1135:on January 22, 2013.
772:. pp. 129–140.
436:Masters of Deception
378:Application security
1176:on 25 October 2010.
1159:on 9 November 2006.
1147:on 27 January 2007.
1123:on 3 February 2015.
413:Chaos Computer Club
148:Black Hat Briefings
22:Part of a series on
685:Tro_Ransom.A virus
679:antivirus software
243:Social engineering
855:. 21 April 2014.
718:Cryptographic API
614:800-90 standard.
602:digital signature
523:
522:
371:Computer security
338:Keystroke logging
1203:
1191:Computer viruses
1177:
1172:. Archived from
1160:
1155:. Archived from
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1143:. Archived from
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1131:. Archived from
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1119:. Archived from
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1103:. Archived from
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1038:. Archived from
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1008:. Archived from
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980:www.f-secure.com
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562:trapdoor one-way
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388:Network security
89:Hacker Manifesto
28:Computer hacking
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18:
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540:and asymmetric
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59:List of hackers
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1094:External links
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1012:on 10 May 2008
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546:authentication
526:Cryptovirology
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221:Hacking tools
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208:Script kiddie
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1196:Cryptography
1174:the original
1170:rosiello.org
1169:
1157:the original
1145:the original
1133:the original
1121:the original
1116:
1105:the original
1069:(2): 67–76.
1066:
1062:
1056:
1044:. Retrieved
1040:the original
1035:
1032:"Securelist"
1026:
1014:. Retrieved
1010:the original
1000:
988:. Retrieved
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970:
961:
949:. Retrieved
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861:. Retrieved
852:
843:
831:. Retrieved
816:
804:. Retrieved
769:
727:
711:
688:
676:
673:Tremor virus
660:
629:
616:
606:Dual EC DRBG
598:Kleptography
593:
590:cryptosystem
585:
573:
571:
550:
530:cryptography
525:
524:
482:
475:
463:
458:Publications
303:Trojan horse
268:HackThisSite
87:
48:
471:Hacker News
358:Infostealer
141:Conferences
95:Hackerspace
1185:Categories
1117:VX Heavens
748:References
661:disclosure
649:ransomware
538:ransomware
536:, such as
328:Logic bomb
323:Ransomware
100:Hacktivism
885:. Wiley.
806:8 October
742:Goat file
714:Microsoft
632:Moti Yung
611:algorithm
582:backdoors
557:antivirus
542:backdoors
446:Blue team
438:(defunct)
432:(defunct)
426:(defunct)
420:(defunct)
408:Anonymous
348:Web shell
198:Crimeware
178:Summercon
126:White hat
116:Black hat
109:Types of
83:Hackathon
44:Phreaking
1083:12990192
984:Archived
942:Archived
857:Archived
833:4 August
827:Archived
800:Archived
796:12179472
736:See also
668:Examples
574:securely
568:Overview
442:Red team
298:Backdoor
173:ShmooCon
121:Grey hat
1046:2 March
990:2 March
951:22 July
863:13 July
645:Bitcoin
641:e-money
626:History
588:, in a
534:malware
532:use in
430:LulzSec
318:Spyware
293:Rootkit
286:Malware
238:Payload
228:Exploit
158:DEF CON
111:hackers
37:History
1081:
1016:23 May
889:
794:
784:
484:Phrack
401:Groups
333:Botnet
273:Zone-H
1079:S2CID
945:(PDF)
934:(PDF)
913:(PDF)
792:S2CID
657:HIPAA
308:Virus
76:ethic
1048:2021
1018:2008
992:2021
953:2016
887:ISBN
865:2017
835:2016
808:2022
782:ISBN
708:CAPI
594:i.e.
586:e.g.
578:PRNG
343:HIDS
313:Worm
74:and
1071:doi
938:HHS
774:doi
716:'s
701:RSA
353:RCE
1187::
1168:.
1115:.
1077:.
1065:.
1034:.
982:.
978:.
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936:.
873:^
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1085:.
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895:.
867:.
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810:.
776::
694:.
514:e
507:t
500:v
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.