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<title>Hardware Trojan</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Hardware Trojan</span></span>

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<p>A <b>Hardware Trojan</b> (<b>HT</b>) is a malicious modification of the <a href="Electronic_circuit" title="Electronic circuit">circuitry</a> of an <a href="Integrated_circuit" title="Integrated circuit">integrated circuit</a>. A hardware <a href="Trojan_horse_(computing)" title="Trojan horse (computing)">Trojan</a> is completely characterized by its physical representation and its behavior. The <a href="Payload_(computing)" title="Payload (computing)">payload</a> of an HT is the entire activity that the Trojan executes when it is triggered. In general, Trojans try to bypass or disable the security fence of a system: for example, leaking confidential information by <a href="Radio_wave" title="Radio wave">radio emission</a>. HTs also could disable, damage or destroy the entire chip or components of it.

</p><p>Hardware Trojans may be introduced as hidden "Front-doors" that are inserted while designing a <a href="Integrated_circuit" title="Integrated circuit">computer chip</a>, by using a pre-made <a href="Application-specific_integrated_circuit" title="Application-specific integrated circuit">application-specific integrated circuit</a> (ASIC) <a href="Semiconductor_intellectual_property_core" title="Semiconductor intellectual property core">semiconductor intellectual property core</a> (IP Core) that have been purchased from a non-reputable source, or inserted internally by a rogue employee, either acting on their own, or on behalf of rogue special interest groups, or state sponsored spying and espionage.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>

</p><p>One paper published by IEEE in 2015 explains how a hardware design containing a Trojan could leak a cryptographic key leaked over an antenna or network connection, provided that the correct "easter egg" trigger is applied to activate the data leak.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>

</p><p>In high security governmental IT departments, hardware Trojans are a well known problem when buying hardware such as: a <a href="KVM_switch" title="KVM switch">KVM switch</a>, keyboards, mice, network cards, or other network equipment. This is especially the case when purchasing such equipment from non-reputable sources that could have placed hardware Trojans to leak keyboard passwords, or provide remote unauthorized entry.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Background">Background</h2></div>

<p>In a diverse global economy, <a href="Outsourcing" title="Outsourcing">outsourcing</a> of production tasks is a common way to lower a product's cost. Embedded hardware devices are not always produced by the firms that design and/or sell them, nor in the same country where they will be used. Outsourced manufacturing can raise doubt about the <a href="Chain_of_custody" title="Chain of custody">evidence</a> for the integrity of the manufactured product (i.e., one's certainty that the end-product has no design modifications compared to its original design). Anyone with access to the manufacturing process could, in theory, introduce some change to the final product. For complex products, small changes with large effects can be difficult to detect.

</p><p>The threat of a serious, malicious, design alteration can be especially relevant to government agencies. Resolving doubt about hardware integrity is one way to reduce <a href="Technology" title="Technology">technology</a> vulnerabilities in the <a href="Military" title="Military">military</a>, <a href="Finance" title="Finance">finance</a>, <a href="Energy" title="Energy">energy</a> and political sectors of an <a href="Economy" title="Economy">economy</a>. Since fabrication of <a href="Integrated_circuits" class="mw-redirect" title="Integrated circuits">integrated circuits</a> in untrustworthy factories is common, advanced detection techniques have emerged to discover when an adversary has hidden additional components in, or otherwise <a href="Sabotage" title="Sabotage">sabotaged</a>, the circuit's function.

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<div class="mw-heading mw-heading2"><h2 id="Characterization_of_hardware_Trojans">Characterization of hardware Trojans</h2></div>

<p>An HT can be characterized by several methods such as by its physical representation, activation phase and its action phase. Alternative methods characterize the HT by trigger, payload and stealth.

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<div class="mw-heading mw-heading3"><h3 id="Physical_characteristics">Physical characteristics</h3></div>

<p>One of this physical Trojan characteristics is the type. The type of a Trojan can be either functional or parametric. A Trojan is functional if the adversary adds or deletes any <a href="Transistor" title="Transistor">transistors</a> or <a href="Logic_gate" title="Logic gate">gates</a> to the original chip design. The other kind of Trojan, the parametric Trojan, modifies the original circuitry, e.g. thinning of wires, weakening of flip-flops or transistors, subjecting the chip to radiation, or using Focused Ion-Beams (FIB) to reduce the reliability of a chip.

</p><p>The size of a Trojan is its physical extension or the number of components it is made of. Because a Trojan can consist of many components, the designer can distribute the parts of a malicious logic on the chip. The additional logic can occupy the chip wherever it is needed to modify, add, or remove a function. Malicious components can be scattered, called loose distribution, or consist of only few components, called tight distribution, so the area is small where the malicious logic occupies the layout of the chip.

</p><p>In some cases, high-effort adversaries in may regenerate the layout so that the placement of the components of the IC is altered. In rare cases the chip dimension is altered. These changes are structural alterations.

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<div class="mw-heading mw-heading3"><h3 id="Activation_characteristics">Activation characteristics</h3></div>

<p>The typical Trojan is condition-based: It is triggered by <a href="Sensors" class="mw-redirect" title="Sensors">sensors</a>, internal logic states, a particular input pattern or an internal counter value. Condition-based Trojans are detectable with power traces to some degree when inactive. That is due to the leakage currents generated by the <a href="https://en.wiktionary.org/wiki/trigger" class="extiw external" title="wikt:trigger">trigger</a> or counter circuit activating the Trojan.

</p><p>Hardware Trojans can be triggered in different ways. A Trojan can be internally activated, which means it monitors one or more signals inside the <a href="Integrated_circuit" title="Integrated circuit">IC</a>. The malicious circuitry could wait for a count down logic an attacker added to the chip, so that the Trojan awakes after a specific time-span. The opposite is externally activated. There can be malicious logic inside a chip, that uses an <a href="Antenna_(radio)" title="Antenna (radio)">antenna</a> or other sensors the adversary can reach from outside the chip. For example, a Trojan could be inside the control system of a cruising <a href="Missile" title="Missile">missile</a>. The owner of the missile does not know, that the enemy will be able to switch off the rockets by <a href="Radio" title="Radio">radio</a>.

</p><p>A Trojan which is always-on can be a reduced wire. A chip that is modified in this way produces errors or fails every time the wire is used intensely. <a href="Always-on" class="mw-redirect" title="Always-on">Always-on circuits</a> are hard to detect with power trace.

</p><p>In this context <a href="Combinational_logic" title="Combinational logic">combinational</a> Trojans and <a href="Sequential_logic" title="Sequential logic">sequential</a> Trojans are distinguished. A combinational Trojan monitors internal signals until a specific condition happens. A sequential Trojan is also an internally activated condition-based circuit, but it monitors the internal signals and searches for sequences not for a specific state or condition like the combinational Trojans do.

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<div class="mw-heading mw-heading4"><h4 id="Cryptographic_key_extraction">Cryptographic key extraction</h4></div>

<p>Extraction of secret keys by means of a hardware Trojan without detecting the Trojan requires that the Trojan uses a random signal or some <a href="Cryptography" title="Cryptography">cryptographic</a> implementation itself.

</p><p>To avoid storing a cryptographic key in the Trojan itself and reduction, a <a href="Physical_unclonable_function" title="Physical unclonable function">physical unclonable function</a> can be used.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Physical unclonable functions are small in size and can have an identical layout while the cryptographic properties are different.

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<div class="mw-heading mw-heading3"><h3 id="Action_characteristics">Action characteristics</h3></div>

<p>A HT could modify the chip's function or could change the chip's parametric properties (e.g. provokes a process delay). Confidential information can also be transmitted to the adversary (transmission of key information).

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<div class="mw-heading mw-heading3"><h3 id="Peripheral_device_hardware_Trojans">Peripheral device hardware Trojans</h3></div>

<p>A relatively new threat vector to networks and network endpoints is a HT appearing as a physical <a href="Peripheral" title="Peripheral">peripheral</a> device that is designed to interact with the network endpoint using the approved peripheral device's communication protocol. For example, a <a href="USB" title="USB">USB</a> keyboard that hides all malicious processing cycles from the target network endpoint to which it is attached by communicating with the target network endpoint using unintended USB channels. Once sensitive data is ex-filtrated from the target network endpoint to the HT, the HT can process the data and decide what to do with the data: store the data to memory for later physical retrieval of the HT or possibly ex-filtrate the data to the internet using wireless or using the compromised network endpoint as a pivot.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Potential_of_threat">Potential of threat</h2></div>

<p>A common Trojan is passive most of the time-span an altered device is in use. If a Trojan is activated the device functionality can be changed, the device can be destroyed or disabled, the device can leak confidential information or the HT may tear down the security and safety of the device. Trojans are stealthy, to avoid detection of the Trojan the precondition for activation is a very rare event. Traditional testing techniques are not sufficient. A manufacturing fault happens at a random position while malicious changes are well placed to avoid detection.

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<div class="mw-heading mw-heading2"><h2 id="Detection">Detection</h2></div>

<div class="mw-heading mw-heading3"><h3 id="Physical_inspection">Physical inspection</h3></div>

<p>First, the molding coat is cut to reveal the circuitry. Then, the engineer repeatedly scans the surface while grinding the layers of the chip. There are several operations to scan the circuitry. Typical visual inspection methods are: scanning optical microscopy (SOM), <a href="Scanning_electron_microscopy" class="mw-redirect" title="Scanning electron microscopy">scanning electron microscopy</a> (SEM),<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> pico-second imaging circuit analysis (PICA), voltage contrast imaging (VCI), <a href="Light_induced_voltage_alteration" class="mw-redirect" title="Light induced voltage alteration">light induced voltage alteration</a> (LIVA) or <a href="Charge_induced_voltage_alteration" class="mw-redirect" title="Charge induced voltage alteration">charge induced voltage alteration</a> (CIVA). To compare the floor plan of the chip has to be compared with the image of the actual chip. This is still quite challenging to do. To detect Trojan hardware which include (crypto) keys which are different, an image diff can be taken to reveal the different structure on the chip. The only known hardware Trojan using unique crypto keys but having the same structure is.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> This property enhances the undetectability of the Trojan.

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<div class="mw-heading mw-heading3"><h3 id="Functional_testing">Functional testing</h3></div>

<p>This detection method stimulates the input ports of a chip and monitors the output to detect manufacturing faults. If the logic values of the output do not match the genuine pattern, then a defect or a Trojan could be found.

</p>

<div class="mw-heading mw-heading3"><h3 id="Built-in_tests">Built-in tests</h3></div>

<p><a href="Built-in_self-test" title="Built-in self-test">Built-in self-test</a> (BIST) and <a href="Design_For_Test" class="mw-redirect" title="Design For Test">Design For Test</a> (DFT) techniques add circuitry (logic) to the chip intended to help verify that the chip, as built, implements its functional specification. The extra logic monitors input stimulus and internal signals or memory states, generally by computing <a href="Checksum" title="Checksum">checksums</a> or by exposing internal registers via a customized <a href="Scan_chain" title="Scan chain">scanning technique</a>. Where DFT usually coordinates with some external testing mechanism, BIST-enabled chips incorporate custom test-pattern generators. BIST functionality often exists to perform at-speed (high speed) verification where it is not possible to use scan chains or other low-speed DFT capabilities. Both methods were originally developed to detect manufacturing errors, but also have the double-edged potential to detect some effects of malicious logic on the chip, or to be exploited by malicious logic to covertly inspect remote state within the chip.

</p><p>Consider how DFT recognizes unintended logic. When driven by DFT inputs, a genuine chip generates a familiar signature, but a defective or altered chip displays an unexpected signature. The signature may consist of any number of data outputs from the chip: an entire scan chain or intermediate data result. In a Trojan-detection context, DFT logic may be regarded as an encryption algorithm: using the DFT input as key to sign a message derived from the behavior of the design under test. In an intrusion-avoidance context, BIST or DFT functions are typically disabled (by hardware-reconfiguration) outside of a manufacturing environment because their access to the chip's internal state can expose its function to covert surveillance or subversive attack.

</p>

<div class="mw-heading mw-heading3"><h3 id="Side_channel_analyses">Side channel analyses</h3></div>

<p>Every device that is electrically active emits different signals like magnetic and electric fields. Those signals – that are caused by the electric activity, can be analyzed to gain information about the state and the data which the device processes. Advanced methods to measure these side-effects have been developed and they are very sensitive (<a href="Side-channel_attack" title="Side-channel attack">side-channel attack</a>). Hence, it is possible to detect tightly coupled Trojans via measurement of these analog signals. The measured values can be used as a signature for the analyzed device. It is also common that a set of measured values is evaluated to avoid measurement errors or other inaccuracies.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>

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<li><a href="Hardware_backdoor" title="Hardware backdoor">Hardware backdoor</a></li>

<li><a href="Hardware_obfuscation" title="Hardware obfuscation">Hardware obfuscation</a></li>

<li><a href="Hardware_security" title="Hardware security">Hardware security</a></li>

<li><a href="Kill_switch" title="Kill switch">Kill switch</a></li>

<li><a href="Physical_unclonable_function" title="Physical unclonable function">Physical unclonable function</a> (PUF)</li>

<li><a href="Security_switch" title="Security switch">Security switch</a></li>

<li><a href="Intel_Management_Engine" title="Intel Management Engine">Intel Management Engine</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2></div>

<ul><li>Mainak Banga and Michael S. Hsiao: A Region Based Approach for the Identification of Hardware Trojans, Bradley Department of Electrical and Computer Engineering, Virginia Tech., Host'08, 2008</li>

<li>A. L. D’Souza and M. Hsiao: Error diagnosis of sequential circuits using region-based model, Proceedings of the IEEE VLSI Design Conference, January, 2001, pp. 103–108.</li>

<li>C. Fagot, O. Gascuel, P. Girard and C. Landrault: On Calculating Efficient LFSR Seeds for Built-In Self Test, Proc. Of European Test Workshop, 1999, pp 7–14</li>

<li>G. Hetherington, T. Fryars, N. Tamarapalli, M. Kassab, A. Hassan and J. Rajski: Logic BIST for large industrial designs, real issues and case studies, ITC, 1999, pp. 358–367</li>

<li>W. T. Cheng, M. Sharma, T. Rinderknecht and C. Hill: Signature Based Diagnosis for Logic BIST, ITC 2006, Oct. 2006, pp. 1–9</li>

<li>Rajat Subhra Chakraborty, Somnath Paul and Swarup Bhunia: On-Demand Transparency for Improving Hardware Trojan Detectability, Department of Electrical Engineering and Computer Science, Case Western Reserve University, Cleveland, OH, USA</li>

<li>Yier Jin and Yiorgos Makris: Hardware Trojan Detection Using Path Delay Fingerprint, Department of Electrical Engineering Yale University, New Haven</li>

<li>Reza Rad, Mohammad Tehranipoor and Jim Plusquellic: Sensitivity Analysis to Hardware Trojans using Power Supply Transient Signals, 1st IEEE International Workshop on Hardware-Oriented Security and Trust (HOST'08), 2008</li>

<li><a href="Dakshi_Agrawal" title="Dakshi Agrawal">Dakshi Agrawal</a>, Selcuk Baktir, Deniz Karakoyunlu, Pankaj Rohatgi and Berk Sunar: Trojan Detection using IC Fingerprinting, IBM T.J. Watson Research Center, Yorktown Heights, Electrical \& Computer Engineering Worcester Polytechnic Institute, Worcester, Massachusetts, Nov 10, 2006</li>

<li>P. Song, F. Stellari, D. Pfeiffer, J. Culp, A. Weger, A. Bonnoit, B. Wisnieff, T. Taubenblatt: MARVEL - Malicious Alteration Recognition and Verification by Emission of Light, IEEE Int. Symp. on Hardware-Oriented Security and Trust (HOST), pp. 117–121, 2011</li>

<li>Xiaoxiao Wang, Mohammad Tehranipoor and Jim Plusquellic: Detecting Malicious Inclusions in Secure Hardware, Challenges and Solutions, 1st IEEE International Workshop on Hardware-Oriented Security and Trust (HOST'08), 2008</li>

<li>Miron Abramovici and Paul Bradley: Integrated Circuit Security - New Threats and Solutions</li>

<li>Zheng Gong and Marc X. Makkes: Hardware Trojan Side-channels Based on Physical Unclonable Functions - Information Security Theory and Practice. Security and Privacy of Mobile Devices in Wireless Communication 2011, Lecture Notes in Computer Science 6633, P294-303.</li>

<li>Vasilios Mavroudis, Andrea Cerulli, Petr Svenda, Dan Cvrcek, Dusan Klinec, George Danezis. A Touch of Evil: High-Assurance Cryptographic Hardware from Untrusted Components. 24th ACM Conference on Computer and Communications Security, Dallas, TX, Oct 30th-Nov 3rd 2017.</li>

<li>Xinmu Wang, HARDWARE TROJAN ATTACKS: THREAT ANALYSIS AND LOW-COST COUNTERMEASURES THROUGH GOLDEN-FREE DETECTION ANDSECURE DESIGN, CASE WESTERN RESERVE UNIVERSITY.</li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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<li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text">Detecting Hardware Trojans with GateLevel InformationFlow Tracking, Wei Hu et al, IEEE publication, 2015</span>

</li>

<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text">Detecting Hardware Trojans with GateLevel InformationFlow Tracking, Wei Hu et al, IEEE publication, 2015</span>

</li>

<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text">Building Trojan Hardware at Home, BlackHat Asia 2014</span>

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<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text">Zeng Gong and Marc X. Makkes "Hardware Trojan side-channels based on physical unclonable functions", WISTP 2011, LNCS 6633 pp.293-303 <style data-mw-deduplicate="TemplateStyles:r1238218222">

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</style><a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-3-642-21040-2_21">10.1007/978-3-642-21040-2_21</a></span>

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<li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text">John Clark, Sylvain Leblanc, Scott Knight, "Hardware Trojan Device Based on Unintended USB Channels," Network and System Security, International Conference on, pp. 1-8, 2009 Third International Conference on Network and System Security, 2009. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FNSS.2009.48">10.1109/NSS.2009.48</a></span>

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<li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><cite id="CITEREFSwapp" class="citation web cs1">Swapp, Susan. <a rel="nofollow" class="external text" href="http://serc.carleton.edu/research_education/geochemsheets/techniques/SEM.html">"Scanning Electron Microscopy (SEM)"</a>. University of Wyoming.</cite></span>

</li>

<li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text">Zeng Gong and Marc X. Makkes "Hardware Trojan side-channels based on physical unclonable functions", WISTP 2011, LNCS 6633 pp.293-303 <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-3-642-21040-2_21">10.1007/978-3-642-21040-2_21</a></span>

</li>

<li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><cite id="CITEREFTehranipoorKoushanfar2010" class="citation journal cs1">Tehranipoor, Mohammad; Koushanfar, Farinaz (2010). "A Survey of Hardware Trojan Taxonomy and Detection". <i>IEEE Design & Test of Computers</i>. <b>27</b>: <span class="nowrap">10–</span>25. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMDT.2010.7">10.1109/MDT.2010.7</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:206459491">206459491</a>.</cite></span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><a rel="nofollow" class="external text" href="http://tehranipoor.ece.ufl.edu/09%20Hardware%20Trojans.pdf">'Hardware Trojan Lecture - University of Florida'</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200717091635/http://tehranipoor.ece.ufl.edu/09%20Hardware%20Trojans.pdf">Archived</a> July 17, 2020, at the <a href="Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li>

<li><a rel="nofollow" class="external text" href="http://www.trust-hub.org/">'Trust-hub' website</a></li></ul>

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</style><div id="Information_security92" style="font-size:114%;margin:0 4em"><a href="Information_security" title="Information security">Information security</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Threat_(computer)" class="mw-redirect" title="Threat (computer)">Threats</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Adware" title="Adware">Adware</a></li>

<li><a href="Advanced_persistent_threat" title="Advanced persistent threat">Advanced persistent threat</a></li>

<li><a href="Arbitrary_code_execution" title="Arbitrary code execution">Arbitrary code execution</a></li>

<li><a href="Backdoor_(computing)" title="Backdoor (computing)">Backdoors</a></li>

<li>Bombs

<li><a href="Logic_bomb" title="Logic bomb">Logic</a></li>

<li><a href="Hardware_backdoor" title="Hardware backdoor">Hardware backdoors</a></li>

<li><a href="Code_injection" title="Code injection">Code injection</a></li>

<li><a href="Crimeware" title="Crimeware">Crimeware</a></li>

<li><a href="Cross-site_scripting" title="Cross-site scripting">Cross-site scripting</a></li>

<li><a href="Cross-site_leaks" title="Cross-site leaks">Cross-site leaks</a></li>

<li><a href="DOM_clobbering" title="DOM clobbering">DOM clobbering</a></li>

<li><a href="History_sniffing" title="History sniffing">History sniffing</a></li>

<li><a href="Cryptojacking" title="Cryptojacking">Cryptojacking</a></li>

<li><a href="Botnet" title="Botnet">Botnets</a></li>

<li><a href="Data_breach" title="Data breach">Data breach</a></li>

<li><a href="Drive-by_download" title="Drive-by download">Drive-by download</a></li>

<li><a href="Browser_Helper_Object" title="Browser Helper Object">Browser Helper Objects</a></li>

<li><a href="Computer_virus" title="Computer virus">Viruses</a></li>

<li><a href="Data_scraping" title="Data scraping">Data scraping</a></li>

<li><a href="Denial-of-service_attack" title="Denial-of-service attack">Denial-of-service attack</a></li>

<li><a href="Eavesdropping" title="Eavesdropping">Eavesdropping</a></li>

<li><a href="Email_fraud" title="Email fraud">Email fraud</a></li>

<li><a href="Email_spoofing" title="Email spoofing">Email spoofing</a></li>

<li><a href="Exploit_(computer_security)" title="Exploit (computer security)">Exploits</a></li>

<li><a href="Dialer#Fraudulent_dialer" title="Dialer">Fraudulent dialers</a></li>

<li><a href="Hacktivism" title="Hacktivism">Hacktivism</a></li>

<li><a href="Infostealer" title="Infostealer">Infostealer</a></li>

<li><a href="Insecure_direct_object_reference" title="Insecure direct object reference">Insecure direct object reference</a></li>

<li><a href="Keystroke_logging" title="Keystroke logging">Keystroke loggers</a></li>

<li><a href="Malware" title="Malware">Malware</a></li>

<li><a href="Payload_(computing)" title="Payload (computing)">Payload</a></li>

<li><a href="Phishing" title="Phishing">Phishing</a>

<ul><li><a href="Voice_phishing" title="Voice phishing">Voice</a></li></ul></li>

<li><a href="Polymorphic_engine" title="Polymorphic engine">Polymorphic engine</a></li>

<li><a href="Privilege_escalation" title="Privilege escalation">Privilege escalation</a></li>

<li><a href="Ransomware" title="Ransomware">Ransomware</a></li>

<li><a href="Rootkit" title="Rootkit">Rootkits</a></li>

<li><a href="Scareware" title="Scareware">Scareware</a></li>

<li><a href="Shellcode" title="Shellcode">Shellcode</a></li>

<li><a href="Spamming" title="Spamming">Spamming</a></li>

<li><a href="Social_engineering_(security)" title="Social engineering (security)">Social engineering</a></li>

<li><a href="Spyware" title="Spyware">Spyware</a></li>

<li><a href="Software_bug" title="Software bug">Software bugs</a></li>

<li><a href="Trojan_horse_(computing)" title="Trojan horse (computing)">Trojan horses</a></li>

<li><a href="Remote_access_trojan" class="mw-redirect" title="Remote access trojan">Remote access trojans</a></li>

<li><a href="Vulnerability_(computer_security)" title="Vulnerability (computer security)">Vulnerability</a></li>

<li><a href="Web_shell" title="Web shell">Web shells</a></li>

<li><a href="Wiper_(malware)" title="Wiper (malware)">Wiper</a></li>

<li><a href="Computer_worm" title="Computer worm">Worms</a></li>

<li><a href="SQL_injection" title="SQL injection">SQL injection</a></li>

<li><a href="Rogue_security_software" title="Rogue security software">Rogue security software</a></li>

<li><a href="Zombie_(computing)" title="Zombie (computing)">Zombie</a></li></ul>

</div></td><td class="noviewer navbox-image" rowspan="3" style="width:1px;padding:0 0 0 2px"><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Defenses</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Application_security" title="Application security">Application security</a>

<ul><li><a href="Secure_coding" title="Secure coding">Secure coding</a></li>

<li>Secure by default</li>

<li><a href="Secure_by_design" title="Secure by design">Secure by design</a>

<ul><li><a href="Misuse_case" title="Misuse case">Misuse case</a></li></ul></li></ul></li>

<li><a href="Computer_access_control" title="Computer access control">Computer access control</a>

<ul><li><a href="Authentication" title="Authentication">Authentication</a>

<ul><li><a href="Multi-factor_authentication" title="Multi-factor authentication">Multi-factor authentication</a></li></ul></li>

<li><a href="Authorization" title="Authorization">Authorization</a></li></ul></li>

<li><a href="Computer_security_software" title="Computer security software">Computer security software</a>

<ul><li><a href="Antivirus_software" title="Antivirus software">Antivirus software</a></li>

<li><a href="Security-focused_operating_system" title="Security-focused operating system">Security-focused operating system</a></li></ul></li>

<li><a href="Data-centric_security" title="Data-centric security">Data-centric security</a></li>

<li><a href="Obfuscation_(software)" title="Obfuscation (software)">Software obfuscation</a></li>

<li><a href="Data_masking" title="Data masking">Data masking</a></li>

<li><a href="Encryption" title="Encryption">Encryption</a></li>

<li><a href="Firewall_(computing)" title="Firewall (computing)">Firewall</a></li>

<li><a href="Intrusion_detection_system" title="Intrusion detection system">Intrusion detection system</a>

<ul><li><a href="Host-based_intrusion_detection_system" title="Host-based intrusion detection system">Host-based intrusion detection system</a> (HIDS)</li>

<li><a href="Anomaly_detection" title="Anomaly detection">Anomaly detection</a></li></ul></li>

<li><a href="Information_security_management" title="Information security management">Information security management</a>

<ul><li><a href="Information_risk_management" class="mw-redirect" title="Information risk management">Information risk management</a></li>

<li><a href="Security_information_and_event_management" title="Security information and event management">Security information and event management</a> (SIEM)</li></ul></li>

<li><a href="Runtime_application_self-protection" title="Runtime application self-protection">Runtime application self-protection</a></li>

<li><a href="Site_isolation" title="Site isolation">Site isolation</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related<br>security<br>topics</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Computer_security" title="Computer security">Computer security</a></li>

<li><a href="Automotive_security" title="Automotive security">Automotive security</a></li>

<li><a href="Cybercrime" title="Cybercrime">Cybercrime</a>

<ul><li><a href="Cybersex_trafficking" title="Cybersex trafficking">Cybersex trafficking</a></li>

<li><a href="Computer_fraud" title="Computer fraud">Computer fraud</a></li></ul></li>

<li><a href="Cybergeddon" title="Cybergeddon">Cybergeddon</a></li>

<li><a href="Cyberterrorism" title="Cyberterrorism">Cyberterrorism</a></li>

<li><a href="Cyberwarfare" title="Cyberwarfare">Cyberwarfare</a></li>

<li><a href="Electronic_warfare" title="Electronic warfare">Electronic warfare</a></li>

<li><a href="Information_warfare" title="Information warfare">Information warfare</a></li>

<li><a href="Internet_security" title="Internet security">Internet security</a></li>

<li><a href="Mobile_security" title="Mobile security">Mobile security</a></li>

<li><a href="Network_security" title="Network security">Network security</a></li>

<li><a href="Copy_protection" title="Copy protection">Copy protection</a></li>

<li><a href="Digital_rights_management" title="Digital rights management">Digital rights management</a></li></ul>

</div></td></tr></tbody></table></div>

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