Key escrow

Last updated

Key escrow (also known as a "fair" cryptosystem) is an arrangement in which the keys needed to decrypt encrypted data are held in escrow so that, under certain circumstances, an authorized third party may gain access to those keys. These third parties may include businesses, who may want access to employees' secure business-related communications, or governments, who may wish to be able to view the contents of encrypted communications (also known as exceptional access). [1]

Contents

The technical problem is a largely structural one. Access to protected information must be provided only to the intended recipient and at least one third party. The third party should be permitted access only under carefully controlled conditions, as for instance, a court order. Thus far, no system design has been shown to meet this requirement fully on a technical basis alone. All proposed systems also require correct functioning of some social linkage, as for instance the process of request for access, examination of request for 'legitimacy' (as by a court), and granting of access by technical personnel charged with access control. All such linkages / controls have serious problems from a system design security perspective. Systems in which the key may not be changed easily are rendered especially vulnerable as the accidental release of the key will result in many devices becoming totally compromised, necessitating an immediate key change or replacement of the system.

On a national level, key escrow is controversial in many countries for at least two reasons. One involves mistrust of the security of the structural escrow arrangement. Many countries have a long history of less than adequate protection of others' information by assorted organizations, public and private, even when the information is held only under an affirmative legal obligation to protect it from unauthorized access. Another is technical concerns for the additional vulnerabilities likely to be introduced by supporting key escrow operations. [1] Thus far, no key escrow system has been designed which meets both objections and nearly all have failed to meet even one.

Key escrow is proactive, anticipating the need for access to keys; a retroactive alternative is key disclosure law, where users are required to surrender keys upon demand by law enforcement, or else face legal penalties. Key disclosure law avoids some of the technical issues and risks of key escrow systems, but also introduces new risks like loss of keys and legal issues such as involuntary self-incrimination. The ambiguous term key recovery is applied to both types of systems.

See also

Related Research Articles

<span class="mw-page-title-main">Encryption</span> Process of converting plaintext to ciphertext

In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can decipher a ciphertext back to plaintext and access the original information. Encryption does not itself prevent interference but denies the intelligible content to a would-be interceptor.

Transport Layer Security (TLS) is a cryptographic protocol designed to provide communications security over a computer network. The protocol is widely used in applications such as email, instant messaging, and voice over IP, but its use in securing HTTPS remains the most publicly visible.

<span class="mw-page-title-main">Clipper chip</span> Encryption device promoted by the NSA in the 1990s

The Clipper chip was a chipset that was developed and promoted by the United States National Security Agency (NSA) as an encryption device that secured "voice and data messages" with a built-in backdoor that was intended to "allow Federal, State, and local law enforcement officials the ability to decode intercepted voice and data transmissions." It was intended to be adopted by telecommunications companies for voice transmission. Introduced in 1993, it was entirely defunct by 1996.

S/MIME is a standard for public-key encryption and signing of MIME data. S/MIME is on an IETF standards track and defined in a number of documents, most importantly RFC 8551. It was originally developed by RSA Data Security, and the original specification used the IETF MIME specification with the de facto industry standard PKCS #7 secure message format. Change control to S/MIME has since been vested in the IETF, and the specification is now layered on Cryptographic Message Syntax (CMS), an IETF specification that is identical in most respects with PKCS #7. S/MIME functionality is built into the majority of modern email software and interoperates between them. Since it is built on CMS, MIME can also hold an advanced digital signature.

The Encrypting File System (EFS) on Microsoft Windows is a feature introduced in version 3.0 of NTFS that provides filesystem-level encryption. The technology enables files to be transparently encrypted to protect confidential data from attackers with physical access to the computer.

End-to-end encryption (E2EE) is a private communication system in which only communicating users can participate. As such, no one, including the communication system provider, telecom providers, Internet providers or malicious actors, can access the cryptographic keys needed to converse.

Secure communication is when two entities are communicating and do not want a third party to listen in. For this to be the case, the entities need to communicate in a way that is unsusceptible to eavesdropping or interception. Secure communication includes means by which people can share information with varying degrees of certainty that third parties cannot intercept what is said. Other than spoken face-to-face communication with no possible eavesdropper, it is probable that no communication is guaranteed to be secure in this sense, although practical obstacles such as legislation, resources, technical issues, and the sheer volume of communication serve to limit surveillance.

<span class="mw-page-title-main">Dorothy E. Denning</span> American information security researcher

Dorothy Elizabeth Denning is a US-American information security researcher known for lattice-based access control (LBAC), intrusion detection systems (IDS), and other cyber security innovations. She published four books and over 200 articles. Inducted into the National Cyber Security Hall of Fame in 2012, she is now Emeritus Distinguished Professor of Defense Analysis, Naval Postgraduate School.

An information security audit is an audit of the level of information security in an organization. It is an independent review and examination of system records, activities, and related documents. These audits are intended to improve the level of information security, avoid improper information security designs, and optimize the efficiency of the security safeguards and security processes. Within the broad scope of auditing information security there are multiple types of audits, multiple objectives for different audits, etc. Most commonly the controls being audited can be categorized as technical, physical and administrative. Auditing information security covers topics from auditing the physical security of data centers to auditing the logical security of databases, and highlights key components to look for and different methods for auditing these areas.

<span class="mw-page-title-main">BitLocker</span> Disk encryption software for Microsoft Windows

BitLocker is a full volume encryption feature included with Microsoft Windows versions starting with Windows Vista. It is designed to protect data by providing encryption for entire volumes. By default, it uses the Advanced Encryption Standard (AES) algorithm in cipher block chaining (CBC) or "xor–encrypt–xor (XEX)-based Tweaked codebook mode with ciphertext Stealing" (XTS) mode with a 128-bit or 256-bit key. CBC is not used over the whole disk; it is applied to each individual sector.

Cryptography is the practice and study of encrypting information, or in other words, securing information from unauthorized access. There are many different cryptography laws in different nations. Some countries prohibit export of cryptography software and/or encryption algorithms or cryptoanalysis methods. Some countries require decryption keys to be recoverable in case of a police investigation.

Disk encryption is a technology which protects information by converting it into code that cannot be deciphered easily by unauthorized people or processes. Disk encryption uses disk encryption software or hardware to encrypt every bit of data that goes on a disk or disk volume. It is used to prevent unauthorized access to data storage.

In computer security, a cold boot attack is a type of side channel attack in which an attacker with physical access to a computer performs a memory dump of a computer's random-access memory (RAM) by performing a hard reset of the target machine. Typically, cold boot attacks are used for retrieving encryption keys from a running operating system for malicious or criminal investigative reasons. The attack relies on the data remanence property of DRAM and SRAM to retrieve memory contents that remain readable in the seconds to minutes following a power switch-off.

<span class="mw-page-title-main">Cryptography</span> Practice and study of secure communication techniques

Cryptography, or cryptology, is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications.

Cloud computing security or, more simply, cloud security, refers to a broad set of policies, technologies, applications, and controls utilized to protect virtualized IP, data, applications, services, and the associated infrastructure of cloud computing. It is a sub-domain of computer security, network security, and, more broadly, information security.

Key disclosure laws, also known as mandatory key disclosure, is legislation that requires individuals to surrender cryptographic keys to law enforcement. The purpose is to allow access to material for confiscation or digital forensics purposes and use it either as evidence in a court of law or to enforce national security interests. Similarly, mandatory decryption laws force owners of encrypted data to supply decrypted data to law enforcement.

<span class="mw-page-title-main">Bullrun (decryption program)</span> Code name of a decryption program run by the NSA

Bullrun is a clandestine, highly classified program to crack encryption of online communications and data, which is run by the United States National Security Agency (NSA). The British Government Communications Headquarters (GCHQ) has a similar program codenamed Edgehill. According to the Bullrun classification guide published by The Guardian, the program uses multiple methods including computer network exploitation, interdiction, industry relationships, collaboration with other intelligence community entities, and advanced mathematical techniques.

<span class="mw-page-title-main">Crypto Wars</span> Attempts to limit access to strong cryptography

Attempts, unofficially dubbed the "Crypto Wars", have been made by the United States (US) and allied governments to limit the public's and foreign nations' access to cryptography strong enough to thwart decryption by national intelligence agencies, especially the National Security Agency (NSA).

Crypto-shredding is the practice of 'deleting' data by deliberately deleting or overwriting the encryption keys. This requires that the data have been encrypted. Data may be considered to exist in three states: data at rest, data in transit and data in use. General data security principles, such as in the CIA triad of confidentiality, integrity, and availability, require that all three states must be adequately protected.

<span class="mw-page-title-main">Human rights and encryption</span> Use of encryption technology to ensure human rights are maintained

Human rights applied to encryption are a concept of freedom of expression, where encryption is a technical resource in the implementation of basic human rights.

References

  1. 1 2 Abelson, Harold; Anderson, Ross; Bellovin, Steven M.; Benaloh, Josh; Blaze, Matt; Diffie, Whitfield; Gilmore, John; Green, Matthew; Landau, Susan; Neumann, Peter G.; Rivest, Ronald L. (2015-11-17). "Keys under doormats: mandating insecurity by requiring government access to all data and communications". Journal of Cybersecurity : tyv009. doi: 10.1093/cybsec/tyv009 . hdl: 1721.1/128748 . ISSN   2057-2085.