Editing Bluetooth (section)

== Security ==

=== Overview ===
{{see also|Mobile security#Attacks based on communication networks}}

Bluetooth implements [[confidentiality]], [[authentication]] and [[key (cryptography)|key]] derivation with custom algorithms based on the [[Secure and Fast Encryption Routine|SAFER+]] [[block cipher]]. Bluetooth key generation is generally based on a Bluetooth PIN, which must be entered into both devices. This procedure might be modified if one of the devices has a fixed PIN (e.g., for headsets or similar devices with a restricted user interface). During pairing, an initialization key or master key is generated, using the E22 algorithm.<ref>{{cite web
|author=Juha T. Vainio
|date=25 May 2000
|title=Bluetooth Security
|publisher=Helsinki University of Technology
|url=http://www.iki.fi/jiitv/bluesec.pdf
|access-date=1 January 2009
|archive-date=25 September 2020
|archive-url=https://web.archive.org/web/20200925110917/http://www.yuuhaw.com/bluesec.pdf
|url-status=live
}}</ref>
The [[E0 (cipher)|E0]] stream cipher is used for encrypting packets, granting confidentiality, and is based on a shared cryptographic secret, namely a previously generated link key or master key. Those keys, used for subsequent encryption of data sent via the air interface, rely on the Bluetooth PIN, which has been entered into one or both devices.

An overview of Bluetooth vulnerabilities exploits was published in 2007 by Andreas Becker.<ref>{{cite web
|author=Andreas Becker
|date=16 August 2007
|title=Bluetooth Security & Hacks
|publisher=Ruhr-Universität Bochum
|url=http://gsyc.es/~anto/ubicuos2/bluetooth_security_and_hacks.pdf
|access-date=10 October 2007
|archive-date=21 March 2016
|archive-url=https://web.archive.org/web/20160321205619/http://gsyc.es/~anto/ubicuos2/bluetooth_security_and_hacks.pdf
|url-status=dead
}}</ref>

In September 2008, the [[National Institute of Standards and Technology]] (NIST) published a Guide to Bluetooth Security as a reference for organizations. It describes Bluetooth security capabilities and how to secure Bluetooth technologies effectively. While Bluetooth has its benefits, it is susceptible to denial-of-service attacks, eavesdropping, man-in-the-middle attacks, message modification, and resource misappropriation. Users and organizations must evaluate their acceptable level of risk and incorporate security into the lifecycle of Bluetooth devices. To help mitigate risks, included in the NIST document are security checklists with guidelines and recommendations for creating and maintaining secure Bluetooth piconets, headsets, and smart card readers.<ref>{{cite web
|author1=Scarfone, K.
|author2=Padgette, J.
|name-list-style=amp
|date=September 2008
|title=Guide to Bluetooth Security
|publisher=National Institute of Standards and Technology
|url=http://csrc.nist.gov/publications/nistpubs/800-121-rev1/sp800-121_rev1.pdf
|access-date=3 July 2013
|archive-date=11 June 2017
|archive-url=https://web.archive.org/web/20170611040534/http://csrc.nist.gov/publications/nistpubs/800-121-rev1/sp800-121_rev1.pdf
|url-status=live
}}</ref>

Bluetooth v2.1&nbsp;– finalized in 2007 with consumer devices first appearing in 2009&nbsp;– makes significant changes to Bluetooth's security, including pairing. See the [[#Pairing mechanisms|pairing mechanisms]] section for more about these changes.

=== Bluejacking ===
{{main|Bluejacking}}
Bluejacking is the sending of either a picture or a message from one user to an unsuspecting user through Bluetooth wireless technology. Common applications include short messages, e.g., "You've just been bluejacked!"<ref>{{cite web|url=http://electronics.howstuffworks.com/bluejacking.htm|title=What is bluejacking?|author=John Fuller|date=28 July 2008 |publisher=howstuffworks|access-date=26 May 2015|archive-date=20 May 2015|archive-url=https://web.archive.org/web/20150520035211/http://electronics.howstuffworks.com/bluejacking.htm|url-status=live}}</ref> Bluejacking does not involve the removal or alteration of any data from the device.<ref>{{Cite web |title=Bluesnarfing vs. Bluejacking: Top 4 Differences |url=https://www.spiceworks.com/it-security/endpoint-security/articles/bluesnarfing-vs-bluejacking/ |access-date=2024-03-06 |website=Spiceworks}}</ref>

Some form of [[Denial-of-service attack|DoS]] is also possible, even in modern devices, by sending unsolicited pairing requests in rapid succession; this becomes disruptive because most systems display a full screen notification for every connection request, interrupting every other activity, especially on less powerful devices.

=== History of security concerns ===

==== 2001–2004 ====
In 2001, Jakobsson and Wetzel from [[Bell Laboratories]] discovered flaws in the Bluetooth pairing protocol and also pointed to vulnerabilities in the encryption scheme.<ref>{{cite news
|title=Security Weaknesses in Bluetooth
|publisher= RSA Security Conf.&nbsp;– Cryptographer's Track
|citeseerx=10.1.1.23.7357
}}</ref> In 2003, Ben and Adam Laurie from A.L. Digital Ltd. discovered that serious flaws in some poor implementations of Bluetooth security may lead to disclosure of personal data.<ref>{{cite web
|title=Bluetooth
|publisher=The Bunker
|url=http://www.thebunker.net/resources/bluetooth
|access-date=1 February 2007
|archive-url = https://web.archive.org/web/20070126012417/http://www.thebunker.net/resources/bluetooth |archive-date = 26 January 2007}}</ref> In a subsequent experiment, Martin Herfurt from the trifinite.group was able to do a field-trial at the [[CeBIT]] fairgrounds, showing the importance of the problem to the world. A new attack called [[Bluebugging|BlueBug]] was used for this experiment.<ref>{{cite web
|title=BlueBug
|publisher=Trifinite.org
|url=http://trifinite.org/trifinite_stuff_bluebug.html
|access-date=1 February 2007
|archive-date=23 December 2018
|archive-url=https://web.archive.org/web/20181223163514/https://trifinite.org/trifinite_stuff_bluebug.html
|url-status=live
}}</ref> In 2004 the first purported [[computer virus|virus]] using Bluetooth to spread itself among mobile phones appeared on the [[Symbian OS]].<ref>{{cite web
|author=John Oates
|date=15 June 2004
|title=Virus attacks mobiles via Bluetooth
|website=The Register
|url=https://www.theregister.co.uk/2004/06/15/symbian_virus/
|access-date=1 February 2007
|archive-date=23 December 2018
|archive-url=https://web.archive.org/web/20181223163603/https://www.theregister.co.uk/2004/06/15/symbian_virus/
|url-status=live
}}</ref>
The virus was first described by [[Kaspersky Lab]] and requires users to confirm the installation of unknown software before it can propagate. The virus was written as a proof-of-concept by a group of virus writers known as "29A" and sent to anti-virus groups. Thus, it should be regarded as a potential (but not real) security threat to Bluetooth technology or [[Symbian OS]] since the virus has never spread outside of this system. In August 2004, a world-record-setting experiment (see also [[Bluetooth sniping]]) showed that the range of Class&nbsp;2 Bluetooth radios could be extended to {{convert|1.78|km|mi|abbr=on}} with directional antennas and signal amplifiers.<ref>{{cite web
|title=Long Distance Snarf
|publisher=Trifinite.org
|url=http://trifinite.org/trifinite_stuff_lds.html
|access-date=1 February 2007
|archive-date=23 December 2018
|archive-url=https://web.archive.org/web/20181223163536/https://trifinite.org/trifinite_stuff_lds.html
|url-status=live
}}</ref>
This poses a potential security threat because it enables attackers to access vulnerable Bluetooth devices from a distance beyond expectation. The attacker must also be able to receive information from the victim to set up a connection. No attack can be made against a Bluetooth device unless the attacker knows its Bluetooth address and which channels to transmit on, although these can be deduced within a few minutes if the device is in use.<ref>{{cite web
|title=Dispelling Common Bluetooth Misconceptions
|publisher=SANS
|url=http://www.sans.edu/research/security-laboratory/article/bluetooth
|access-date=9 July 2014
|archive-date=14 July 2014
|archive-url=https://web.archive.org/web/20140714150109/http://www.sans.edu/research/security-laboratory/article/bluetooth
|url-status=dead
}}</ref>

==== 2005 ====
In January 2005, a mobile [[malware]] worm known as Lasco surfaced. The worm began targeting mobile phones using [[Symbian OS]] ([[S60 (software platform)|Series 60 platform]]) using Bluetooth enabled devices to replicate itself and spread to other devices. The worm is self-installing and begins once the mobile user approves the transfer of the file (Velasco.sis) from another device. Once installed, the worm begins looking for other Bluetooth enabled devices to infect. Additionally, the worm infects other [[.SIS]]&nbsp;files on the device, allowing replication to another device through the use of removable media ([[Secure Digital]], [[CompactFlash]], etc.). The worm can render the mobile device unstable.<ref>{{cite web
 |url          = http://www.f-secure.com/v-descs/lasco_a.shtml
 |title        = F-Secure Malware Information Pages: Lasco.A
 |publisher    = F-Secure.com
 |access-date   = 5 May 2008
|archive-url  = https://web.archive.org/web/20080517091014/http://www.f-secure.com/v-descs/lasco_a.shtml
 |archive-date = 17 May 2008
|url-status     = dead
}}</ref>

In April 2005, [[University of Cambridge]] security researchers published results of their actual implementation of passive attacks against the [[Personal identification number|PIN-based]] pairing between commercial Bluetooth devices. They confirmed that attacks are practicably fast, and the Bluetooth symmetric key establishment method is vulnerable. To rectify this vulnerability, they designed an implementation that showed that stronger, asymmetric key establishment is feasible for certain classes of devices, such as mobile phones.<ref>{{cite web
|author1=Ford-Long Wong |author2=Frank Stajano |author3=Jolyon Clulow |date=April 2005
|title=Repairing the Bluetooth pairing protocol
|publisher=University of Cambridge Computer Laboratory
|url=http://www.cl.cam.ac.uk/~fw242/publications/2005-WongStaClu-bluetooth.pdf
|access-date=1 February 2007
|archive-url = https://web.archive.org/web/20070616082657/http://www.cl.cam.ac.uk/~fw242/publications/2005-WongStaClu-bluetooth.pdf <!-- Bot retrieved archive --> |archive-date = 16 June 2007}}</ref>

In June 2005, Yaniv Shaked<ref>{{cite web |url=http://www.eng.tau.ac.il/~shakedy |title=Yaniv Shaked's Homepage |access-date=6 November 2007 |url-status=dead |archive-url=https://web.archive.org/web/20071109192150/http://www.eng.tau.ac.il/~shakedy/ |archive-date=9 November 2007 }}</ref> and Avishai Wool<ref>{{cite web|url=http://www.eng.tau.ac.il/~yash/|title=Avishai Wool – אבישי וול|website=tau.ac.il|access-date=4 June 2015|archive-date=23 December 2018|archive-url=https://web.archive.org/web/20181223163419/http://www.eng.tau.ac.il/~yash/|url-status=live}}</ref> published a paper describing both passive and active methods for obtaining the PIN for a Bluetooth link. The passive attack allows a suitably equipped attacker to eavesdrop on communications and spoof if the attacker was present at the time of initial pairing. The active method makes use of a specially constructed message that must be inserted at a specific point in the protocol, to make the master and slave repeat the pairing process. After that, the first method can be used to crack the PIN. This attack's major weakness is that it requires the user of the devices under attack to re-enter the PIN during the attack when the device prompts them to. Also, this active attack probably requires custom hardware, since most commercially available Bluetooth devices are not capable of the timing necessary.<ref>{{cite web
|author1=Yaniv Shaked
|author2=Avishai Wool
|date=2 May 2005
|title=Cracking the Bluetooth PIN
|publisher=School of Electrical Engineering Systems, Tel Aviv University
|url=http://www.eng.tau.ac.il/~yash/shaked-wool-mobisys05/
|access-date=1 February 2007
|archive-date=23 December 2018
|archive-url=https://web.archive.org/web/20181223163532/http://www.eng.tau.ac.il/~yash/shaked-wool-mobisys05/
|url-status=live
}}</ref>

In August 2005, police in [[Cambridgeshire]], England, issued warnings about thieves using Bluetooth enabled phones to track other devices left in cars. Police are advising users to ensure that any mobile networking connections are de-activated if laptops and other devices are left in this way.<ref>{{cite news
|title=Phone pirates in seek and steal mission
|newspaper=Cambridge Evening News
|url=http://www.cambridge-news.co.uk/news/region_wide/2005/08/17/06967453-8002-45f8-b520-66b9bed6f29f.lpf
|archive-url=https://web.archive.org/web/20070717035938/http://www.cambridge-news.co.uk/news/region_wide/2005/08/17/06967453-8002-45f8-b520-66b9bed6f29f.lpf
|archive-date=17 July 2007
|access-date=4 February 2008
}}</ref>

==== 2006 ====
In April 2006, researchers from [[Secure Network]] and [[F-Secure]] published a report that warns of the large number of devices left in a visible state, and issued statistics on the spread of various Bluetooth services and the ease of spread of an eventual Bluetooth worm.<ref>{{cite web
|title=Going Around with Bluetooth in Full Safety
|url=http://www.securenetwork.it/bluebag_brochure.pdf
|archive-url=https://web.archive.org/web/20060610072813/http://www.securenetwork.it/bluebag_brochure.pdf
|url-status=dead
|archive-date=10 June 2006
|publisher=F-Secure
|date=May 2006
|access-date=4 February 2008
}}</ref>

In October 2006, at the Luxembourgish Hack.lu Security Conference, Kevin Finistere and Thierry Zoller demonstrated and released a remote root shell via Bluetooth on Mac OS X v10.3.9 and v10.4. They also demonstrated the first Bluetooth PIN and Linkkeys cracker, which is based on the research of Wool and Shaked.<ref>{{cite web |last1=Finistere & Zoller |title=All your Bluetooth is belong to us |url=http://archive.hack.lu/2006/Zoller_hack_lu_2006.pdf |website=archive.hack.lu |access-date=20 September 2017 |archive-date=23 December 2018 |archive-url=https://web.archive.org/web/20181223163448/http://archive.hack.lu/2006/Zoller_hack_lu_2006.pdf |url-status=live }}</ref>

==== 2017 ====
In April 2017, security researchers at Armis discovered multiple exploits in the Bluetooth software in various platforms, including [[Microsoft Windows]], [[Linux]], Apple [[iOS]], and Google [[Android (operating system)|Android]]. These vulnerabilities are collectively called "[[BlueBorne]]". The exploits allow an attacker to connect to devices or systems without authentication and can give them "virtually full control over the device". Armis contacted Google, Microsoft, Apple, Samsung and Linux developers allowing them to patch their software before the coordinated announcement of the vulnerabilities on 12 September 2017.<ref>{{Cite news|url=https://www.armis.com/blueborne/#/technical|title=BlueBorne Information from the Research Team – Armis Labs|work=armis|access-date=20 September 2017|archive-date=21 September 2017|archive-url=https://web.archive.org/web/20170921075121/https://www.armis.com/blueborne/#/technical|url-status=live}}</ref>

==== 2018 ====
In July 2018, Lior Neumann and [[Eli Biham]], researchers at the Technion – Israel Institute of Technology identified a security vulnerability in the latest Bluetooth pairing procedures: Secure Simple Pairing and LE Secure Connections.<ref>{{cite web|url=https://www.forbes.com/sites/thomasbrewster/2018/07/24/bluetooth-hack-warning-for-iphone-android-and-windows|title=Update Your iPhones And Androids Now If You Don't Want Your Bluetooth Hacked|website=Forbes|date=24 July 2019|access-date=26 September 2019|archive-date=26 September 2019|archive-url=https://web.archive.org/web/20190926093726/https://www.forbes.com/sites/thomasbrewster/2018/07/24/bluetooth-hack-warning-for-iphone-android-and-windows|url-status=live}}</ref><ref>{{cite book|chapter-url=https://eprint.iacr.org/2019/1043|first1=Lior|last1=Neumann|first2=Eli|last2=Biham|chapter=Breaking the Bluetooth Pairing – the Fixed Coordinate Invalid Curve Attack |title=Selected Areas in Cryptography – SAC 2019|series=Lecture Notes in Computer Science|year=2020|volume=11959|pages=250–273|publisher=Technion – Israel Institute of Technology|doi=10.1007/978-3-030-38471-5_11|isbn=978-3-030-38470-8|s2cid=51757249|access-date=26 September 2019|archive-date=18 September 2019|archive-url=https://web.archive.org/web/20190918215324/https://eprint.iacr.org/2019/1043|url-status=live|issn=0302-9743}}</ref>

Also, in October 2018, Karim Lounis, a network security researcher at Queen's University, identified a security vulnerability, called CDV (Connection Dumping Vulnerability), on various Bluetooth devices that allows an attacker to tear down an existing Bluetooth connection and cause the deauthentication and disconnection of the involved devices. The researcher demonstrated the attack on various devices of different categories and from different manufacturers.<ref>{{cite book|chapter-url=https://link.springer.com/chapter/10.1007/978-3-030-12143-3_16|first1=Karim|last1=Lounis|first2=Mohammad|last2=Zulkernine|chapter=Connection Dumping Vulnerability Affecting Bluetooth Availability|title=13th International Conference on Risks and Security of Internet and Systems – CRiSIS 2018|series=Lecture Notes in Computer Science|year=2019|volume=11391|pages=188–204|publisher=Springer|doi=10.1007/978-3-030-12143-3_16|isbn=978-3-030-12142-6|s2cid=59248863|access-date=30 August 2021|archive-date=30 August 2021|archive-url=https://web.archive.org/web/20210830005951/https://link.springer.com/chapter/10.1007/978-3-030-12143-3_16|url-status=live}}</ref>

==== 2019 ====

In August 2019, security researchers at the [[Singapore University of Technology and Design]], Helmholtz Center for Information Security, and [[University of Oxford]] discovered a vulnerability, called KNOB (Key Negotiation of Bluetooth) in the key negotiation that would "brute force the negotiated encryption keys, decrypt the eavesdropped ciphertext, and inject valid encrypted messages (in real-time)".
<ref>{{cite web|url=https://www.forbes.com/sites/zakdoffman/2019/08/15/critical-new-bluetooth-security-issue-leaves-your-devices-and-data-open-to-attack|title=New Critical Bluetooth Security Issue Exposes Millions of Devices To Attack|website=Forbes|date=15 August 2019|access-date=20 August 2019|archive-date=20 August 2019|archive-url=https://web.archive.org/web/20190820200938/https://www.forbes.com/sites/zakdoffman/2019/08/15/critical-new-bluetooth-security-issue-leaves-your-devices-and-data-open-to-attack|url-status=live}}</ref>
<ref>{{cite book|url=https://www.usenix.org/system/files/sec19-antonioli.pdf|title=The KNOB is Broken: Exploiting Low Entropy in the Encryption Key Negotiation of Bluetooth BR/EDR|first1=Daniele|last1=Antonioli|first2=Nils Ole|last2=Tippenhauer|first3=Kasper B.|last3=Rasmussen|publisher=University of Oxford|location=Santa Clara|date=15 August 2019|isbn=9781939133069|access-date=14 June 2021|archive-date=16 April 2021|archive-url=https://web.archive.org/web/20210416163953/https://www.usenix.org/system/files/sec19-antonioli.pdf|url-status=live}}</ref> Google released an [[Android (operating system)|Android]] security patch on 5 August 2019, which removed this vulnerability.<ref>{{cite web|url=https://source.android.com/security/bulletin/2019-08-01.html|title=Android Security Bulletin—August 2019|access-date=5 June 2022}}</ref>

==== 2023 ====

In November 2023, researchers from [[Eurecom]] revealed a new class of attacks known as BLUFFS (Bluetooth Low Energy Forward and Future Secrecy Attacks). These 6 new attacks expand on and work in conjunction with the previously known KNOB and BIAS (Bluetooth Impersonation AttackS) attacks. While the previous KNOB and BIAS attacks allowed an attacker to decrypt and spoof Bluetooth packets within a session, BLUFFS extends this capability to all sessions generated by a device (including past, present, and future). All devices running Bluetooth versions 4.2 up to and including 5.4 are affected.<ref>{{cite web|url=https://www.bleepingcomputer.com/news/security/new-bluffs-attack-lets-attackers-hijack-bluetooth-connections/|title=New BLUFFS attack lets attackers hijack Bluetooth connections|access-date=1 December 2023}}</ref><ref>{{cite report|doi=10.1145/3576915.3623066|chapter=BLUFFS: Bluetooth Forward and Future Secrecy Attacks and Defenses |title=Proceedings of the 2023 ACM SIGSAC Conference on Computer and Communications Security |date=2023 |last1=Antonioli |first1=Daniele |pages=636–650 |isbn=979-8-4007-0050-7 }}</ref>