{"id":11064,"date":"2025-01-06T09:00:00","date_gmt":"2025-01-06T08:00:00","guid":{"rendered":"https:\/\/www.blog.bim.finance\/?p=11064"},"modified":"2025-01-03T11:05:22","modified_gmt":"2025-01-03T10:05:22","slug":"quest-ce-quune-attaque-a-51","status":"publish","type":"post","link":"https:\/\/www.blog.bim.finance\/en\/quest-ce-quune-attaque-a-51\/","title":{"rendered":"Qu\u2019est-ce qu\u2019une attaque \u00e0 51 % ?"},"content":{"rendered":"<div data-elementor-type=\"wp-post\" data-elementor-id=\"11064\" class=\"elementor elementor-11064\" data-elementor-post-type=\"post\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-4dd4b63 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"4dd4b63\" data-element_type=\"section\" data-e-type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-5d9bd31\" data-id=\"5d9bd31\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-2aeacc2 elementor-widget elementor-widget-heading\" data-id=\"2aeacc2\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Qu\u2019est-ce qu\u2019une attaque \u00e0 51 % ?<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-393feb9 elementor-widget elementor-widget-text-editor\" data-id=\"393feb9\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p data-pm-slice=\"1 1 []\"><strong>Une attaque \u00e0 51 % est une menace majeure pour les r\u00e9seaux blockchain.<\/strong> Elle survient lorsqu&rsquo;un individu ou un groupe de mineurs malveillants obtient le contr\u00f4le de plus de 50 % de la puissance de calcul (preuve de travail, ou PoW) ou des n\u0153uds validateurs (preuve d\u2019enjeu, ou PoS) d&rsquo;une blockchain.<\/p><p data-pm-slice=\"1 1 []\">Cette situation permet \u00e0 l&rsquo;attaquant de manipuler le r\u00e9seau, de censurer certaines transactions, d\u2019emp\u00eacher leur confirmation et, dans certains cas, de d\u00e9penser plusieurs fois la m\u00eame cryptomonnaie, un ph\u00e9nom\u00e8ne connu sous le nom de double d\u00e9pense.<\/p><p data-pm-slice=\"1 1 []\">Ces attaques, bien que rares sur les grandes blockchains, peuvent causer des d\u00e9g\u00e2ts majeurs sur les r\u00e9seaux moins populaires ou r\u00e9cemment cr\u00e9\u00e9s.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4ffe78d elementor-widget elementor-widget-heading\" data-id=\"4ffe78d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Fonctionnement d'une blockchain<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d8300b0 elementor-widget elementor-widget-text-editor\" data-id=\"d8300b0\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p data-pm-slice=\"1 1 []\">Pour comprendre comment une attaque \u00e0 51 % est possible, il est essentiel de saisir les bases du fonctionnement d\u2019une blockchain.<\/p><p>Une blockchain est un registre distribu\u00e9 o\u00f9 les transactions sont enregistr\u00e9es sous forme de blocs li\u00e9s cryptographiquement. Chaque bloc contient une s\u00e9rie de transactions valid\u00e9es par des mineurs ou des validateurs selon le m\u00e9canisme de consensus choisi. Ces m\u00e9canismes garantissent l&rsquo;int\u00e9grit\u00e9 et la s\u00e9curit\u00e9 des donn\u00e9es.<\/p><ul data-spread=\"false\"><li><p><a href=\"https:\/\/www.blog.bim.finance\/en\/quest-ce-que-le-proof-of-work\/\"><strong>Preuve de travail (PoW)<\/strong><\/a> : Les mineurs effectuent des calculs complexes pour valider les blocs et re\u00e7oivent des r\u00e9compenses. Le r\u00e9seau s\u2019accorde sur la cha\u00eene la plus longue, c\u2019est-\u00e0-dire celle avec le plus de preuves de travail accumul\u00e9es. Ce m\u00e9canisme demande des ressources importantes, ce qui contribue \u00e0 sa s\u00e9curit\u00e9.<\/p><\/li><li><p><a href=\"https:\/\/www.blog.bim.finance\/en\/quest-ce-que-le-proof-of-stake\/\"><strong>Preuve d\u2019enjeu (PoS)<\/strong><\/a> : Les validateurs participent \u00e0 la validation des blocs proportionnellement \u00e0 la quantit\u00e9 de cryptomonnaie qu\u2019ils poss\u00e8dent et mettent en jeu. Ce mod\u00e8le limite les besoins \u00e9nerg\u00e9tiques mais repose sur une r\u00e9partition \u00e9quitable des jetons.<\/p><\/li><\/ul><p>Les blockchains sont con\u00e7ues pour \u00eatre d\u00e9centralis\u00e9es, ce qui signifie que <strong>le pouvoir est r\u00e9parti entre de nombreux participants<\/strong>. Cependant, <strong>si une seule entit\u00e9 acquiert plus de 50 %<\/strong> de la puissance de calcul ou des n\u0153uds validateurs, elle peut manipuler le r\u00e9seau.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-efd5ada elementor-widget elementor-widget-heading\" data-id=\"efd5ada\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">M\u00e9canisme d'une attaque \u00e0 51 %<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7602103 elementor-widget elementor-widget-text-editor\" data-id=\"7602103\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p data-pm-slice=\"1 1 []\">Voici les \u00e9tapes typiques d&rsquo;une attaque \u00e0 51 % dans une blockchain fonctionnant sous preuve de travail :<\/p><ol start=\"1\" data-spread=\"true\"><li><p><strong>Contr\u00f4le de la puissance de calcul<\/strong> L\u2019attaquant obtient plus de la moiti\u00e9 de la puissance de calcul totale du r\u00e9seau. Cela peut \u00eatre fait en centralisant des ressources, en louant de la puissance de calcul via des services de minage ou en exploitant une blockchain \u00e0 faible adoption.<\/p><\/li><li><p><strong>Cr\u00e9ation d\u2019une cha\u00eene alternative<\/strong> Pendant que la cha\u00eene principale poursuit son activit\u00e9 normale, l\u2019attaquant commence \u00e0 miner en priv\u00e9 une cha\u00eene parall\u00e8le contenant des transactions frauduleuses. Cette cha\u00eene reste secr\u00e8te jusqu&rsquo;\u00e0 un moment opportun.<\/p><\/li><li><p><strong>Double d\u00e9pense<\/strong> L&rsquo;attaquant effectue une transaction l\u00e9gitime sur la cha\u00eene publique (par exemple, acheter un bien ou convertir des cryptos). Ensuite, il inclut une transaction diff\u00e9rente dans sa cha\u00eene priv\u00e9e, renvoyant les fonds \u00e0 sa propre adresse.<\/p><\/li><li><p><strong>Publication de la cha\u00eene alternative<\/strong> Une fois que la cha\u00eene alternative d\u00e9passe la cha\u00eene publique en longueur, elle devient la cha\u00eene valide selon les r\u00e8gles de consensus. Les transactions l\u00e9gitimes sont annul\u00e9es, permettant \u00e0 l&rsquo;attaquant de conserver \u00e0 la fois le bien achet\u00e9 et la cryptomonnaie.<\/p><\/li><\/ol><p>Ce processus peut gravement affecter la confiance des utilisateurs et entra\u00eener une chute drastique de la valeur de la cryptomonnaie attaqu\u00e9e.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4ae4831 elementor-widget elementor-widget-heading\" data-id=\"4ae4831\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h4 class=\"elementor-heading-title elementor-size-default\">Bitcoin Gold (2018, 2020)<\/h4>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dbdcff8 elementor-widget elementor-widget-text-editor\" data-id=\"dbdcff8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>En 2018, Bitcoin Gold a \u00e9t\u00e9 victime d&rsquo;une attaque de grande envergure. <strong>Un groupe d&rsquo;attaquants a pris le contr\u00f4le de plus de 50 % de la puissance de calcul du r\u00e9seau<\/strong>, ce qui leur a permis d&rsquo;effectuer des doubles d\u00e9penses sur plusieurs plateformes d&rsquo;\u00e9change.<\/p><p>Les pertes totales ont \u00e9t\u00e9 estim\u00e9es \u00e0 <strong>environ 18 millions de dollars.<\/strong> Une fois r\u00e9v\u00e9l\u00e9e, cette attaque a gravement endommag\u00e9 la r\u00e9putation de Bitcoin Gold, entra\u00eenant une chute significative de sa valeur.<\/p><p>En 2020, une attaque similaire a eu lieu, mettant en \u00e9vidence les failles persistantes dans la s\u00e9curit\u00e9 du r\u00e9seau. Les mineurs honn\u00eates ont tent\u00e9 de r\u00e9agir en augmentant la d\u00e9centralisation, mais la confiance des utilisateurs dans la cryptomonnaie n&rsquo;a jamais \u00e9t\u00e9 pleinement r\u00e9tablie.<\/p><p>Ces \u00e9v\u00e9nements ont pouss\u00e9 la communaut\u00e9 \u00e0 envisager des changements dans le protocole, mais avec des r\u00e9sultats mitig\u00e9s.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-fdff16c elementor-widget elementor-widget-heading\" data-id=\"fdff16c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h4 class=\"elementor-heading-title elementor-size-default\">Ethereum Classic (2019) <\/h4>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-80815db elementor-widget elementor-widget-text-editor\" data-id=\"80815db\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p data-pm-slice=\"1 1 [&quot;ordered_list&quot;,{&quot;spread&quot;:true,&quot;startingNumber&quot;:1,&quot;start&quot;:4403,&quot;end&quot;:6720},&quot;regular_list_item&quot;,{&quot;start&quot;:5311,&quot;end&quot;:6031}]\">En janvier 2019, Ethereum Classic a \u00e9t\u00e9 la cible d&rsquo;une attaque \u00e0 51 % qui a dur\u00e9 plusieurs jours.<\/p><p data-pm-slice=\"1 1 [&quot;ordered_list&quot;,{&quot;spread&quot;:true,&quot;startingNumber&quot;:1,&quot;start&quot;:4403,&quot;end&quot;:6720},&quot;regular_list_item&quot;,{&quot;start&quot;:5311,&quot;end&quot;:6031}]\">Les attaquants ont r\u00e9ussi \u00e0 r\u00e9organiser la cha\u00eene, ce qui leur a permis de <strong>doublement d\u00e9penser des fonds pour un montant de 1,1 million de dollars.<\/strong> L\u2019attaque a principalement vis\u00e9 des plateformes d\u2019\u00e9change, provoquant des suspensions temporaires des d\u00e9p\u00f4ts et des retraits pour Ethereum Classic.\u00a0<\/p><p data-pm-slice=\"1 1 [&quot;ordered_list&quot;,{&quot;spread&quot;:true,&quot;startingNumber&quot;:1,&quot;start&quot;:4403,&quot;end&quot;:6720},&quot;regular_list_item&quot;,{&quot;start&quot;:5311,&quot;end&quot;:6031}]\">Cette attaque a soulev\u00e9 des questions sur la viabilit\u00e9 \u00e0 long terme des blockchains plus petites face \u00e0 de telles menaces. Les d\u00e9veloppeurs ont intensifi\u00e9 leurs efforts pour renforcer la s\u00e9curit\u00e9, mais Ethereum Classic reste vuln\u00e9rable en raison de sa taille r\u00e9duite par rapport \u00e0 Ethereum.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-85173f8 elementor-widget elementor-widget-heading\" data-id=\"85173f8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h4 class=\"elementor-heading-title elementor-size-default\">Verge (2018) <\/h4>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5dd7c68 elementor-widget elementor-widget-text-editor\" data-id=\"5dd7c68\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p data-pm-slice=\"1 1 [&quot;ordered_list&quot;,{&quot;spread&quot;:true,&quot;startingNumber&quot;:1,&quot;start&quot;:4403,&quot;end&quot;:6720},&quot;regular_list_item&quot;,{&quot;start&quot;:6033,&quot;end&quot;:6720}]\">Verge, une cryptomonnaie ax\u00e9e sur la confidentialit\u00e9, a subi deux attaques \u00e0 51 % en l&rsquo;espace de quelques mois.<\/p><p data-pm-slice=\"1 1 [&quot;ordered_list&quot;,{&quot;spread&quot;:true,&quot;startingNumber&quot;:1,&quot;start&quot;:4403,&quot;end&quot;:6720},&quot;regular_list_item&quot;,{&quot;start&quot;:6033,&quot;end&quot;:6720}]\">En avril 2018, les attaquants ont exploit\u00e9 une faille dans l&rsquo;algorithme d&rsquo;ajustement de difficult\u00e9 de Verge, leur permettant de miner plusieurs blocs frauduleux en un temps record. La deuxi\u00e8me attaque, en mai 2018, a r\u00e9utilis\u00e9 une variante de la m\u00eame faille.<\/p><p data-pm-slice=\"1 1 [&quot;ordered_list&quot;,{&quot;spread&quot;:true,&quot;startingNumber&quot;:1,&quot;start&quot;:4403,&quot;end&quot;:6720},&quot;regular_list_item&quot;,{&quot;start&quot;:6033,&quot;end&quot;:6720}]\"><strong>Ces attaques ont entra\u00een\u00e9 la perte de millions de tokens Verge<\/strong>, r\u00e9duisant la confiance des investisseurs et for\u00e7ant l&rsquo;\u00e9quipe de d\u00e9veloppement \u00e0 revoir en urgence l&rsquo;infrastructure du r\u00e9seau. Cette s\u00e9rie d\u2019\u00e9v\u00e9nements a illustr\u00e9 les dangers de failles non corrig\u00e9es dans des syst\u00e8mes complexes.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4dc52dd elementor-widget elementor-widget-heading\" data-id=\"4dc52dd\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h5 class=\"elementor-heading-title elementor-size-default\">Risques et cons\u00e9quences<\/h5>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-832e00e elementor-widget elementor-widget-text-editor\" data-id=\"832e00e\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<ul data-spread=\"false\" data-pm-slice=\"3 3 []\"><li><p><strong>Double d\u00e9pense<\/strong> : L&rsquo;attaquant peut d\u00e9penser la m\u00eame cryptomonnaie deux fois, ce qui nuit directement aux parties commerciales impliqu\u00e9es.<\/p><\/li><li><p><strong>Perte de confiance<\/strong> : Une attaque r\u00e9ussie compromet la r\u00e9putation et la valeur de la blockchain attaqu\u00e9e. Les utilisateurs peuvent abandonner le r\u00e9seau, entra\u00eenant une baisse d\u2019activit\u00e9.<\/p><\/li><li><p><strong>Censure<\/strong> : L&rsquo;attaquant peut emp\u00eacher certaines transactions d&rsquo;\u00eatre confirm\u00e9es, compromettant l&rsquo;\u00e9quit\u00e9 et la neutralit\u00e9 du r\u00e9seau.<\/p><\/li><li><p><strong>Effondrement \u00e9conomique<\/strong> : La cryptomonnaie attaqu\u00e9e peut perdre rapidement de la valeur, affectant les investisseurs et les entreprises associ\u00e9es.<\/p><\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1f5724e elementor-widget elementor-widget-heading\" data-id=\"1f5724e\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h6 class=\"elementor-heading-title elementor-size-default\">Comment pr\u00e9venir une attaque \u00e0 51 % ?<\/h6>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dbdddc8 elementor-widget elementor-widget-text-editor\" data-id=\"dbdddc8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><strong>D\u00e9centralisation accrue<\/strong> Une blockchain tr\u00e8s d\u00e9centralis\u00e9e, avec de nombreux n\u0153uds actifs r\u00e9partis g\u00e9ographiquement, r\u00e9duit le risque d&rsquo;une concentration de pouvoir.<\/p><p><strong>M\u00e9canismes de s\u00e9curit\u00e9 avanc\u00e9s<\/strong><\/p><ul data-spread=\"false\"><li><p>Checkpoints : Points fixes dans la blockchain pour emp\u00eacher les r\u00e9organisations importantes.<\/p><\/li><li><p>Protocoles hybrides : Combinaison de PoW et PoS pour \u00e9quilibrer s\u00e9curit\u00e9 et d\u00e9centralisation.<\/p><\/li><\/ul><p><strong>Surveillance r\u00e9guli\u00e8re<\/strong> Les d\u00e9veloppeurs et la communaut\u00e9 doivent surveiller les anomalies dans l\u2019activit\u00e9 du r\u00e9seau. Un monitoring proactif peut d\u00e9tecter une activit\u00e9 suspecte avant qu&rsquo;elle ne devienne critique.<\/p><p><strong>Adoption d\u2019algorithmes r\u00e9sistants<\/strong> Certains algorithmes, comme le Proof of Stake, rendent ce type d\u2019attaque co\u00fbteux et peu rentable, surtout lorsque des m\u00e9canismes punitifs pour les validateurs malhonn\u00eates sont inclus.<\/p><p><strong>Participation communautaire<\/strong> Les utilisateurs doivent \u00eatre impliqu\u00e9s dans le processus de gouvernance pour renforcer la transparence et \u00e9viter la centralisation.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cee6b69 elementor-widget elementor-widget-text-editor\" data-id=\"cee6b69\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p data-pm-slice=\"1 1 []\">L\u2019attaque \u00e0 51 % est une menace significative pour les blockchains, en particulier celles avec une faible adoption ou un faible taux de d\u00e9centralisation.<\/p><p data-pm-slice=\"1 1 []\">Cependant, les grandes blockchains comme Bitcoin et Ethereum sont relativement s\u00e9curis\u00e9es gr\u00e2ce \u00e0 leur taille et \u00e0 leur r\u00e9partition de puissance. Les efforts continus pour renforcer la d\u00e9centralisation et adopter des protocoles avanc\u00e9s constituent les meilleurs moyens de pr\u00e9venir ces attaques.<\/p><p data-pm-slice=\"1 1 []\">Comprendre les m\u00e9canismes sous-jacents \u00e0 ces attaques est essentiel pour garantir la r\u00e9silience des syst\u00e8mes blockchain dans un monde en constante \u00e9volution.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>","protected":false},"excerpt":{"rendered":"<p>Les blockchains sont souvent per\u00e7ues comme des syst\u00e8mes inviolables offrant une s\u00e9curit\u00e9 in\u00e9gal\u00e9e pour les transactions num\u00e9riques. Cependant, cette technologie n\u2019est pas sans faille. L\u2019attaque \u00e0 51 % est l\u2019une des menaces les plus redout\u00e9es pour les r\u00e9seaux blockchain, capable de perturber leur fonctionnement fondamental. Dans cet article, nous allons explorer en d\u00e9tail ce qu\u2019est une attaque \u00e0 51 %, comment elle se produit, ses cons\u00e9quences, et des exemples concrets tir\u00e9s de l\u2019histoire des cryptomonnaies.<\/p>","protected":false},"author":4,"featured_media":11065,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mo_disable_npp":"","_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[7,16],"tags":[],"ppma_author":[147],"class_list":["post-11064","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blockchain","category-lexique"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Qu\u2019est-ce qu\u2019une attaque \u00e0 51 % ?<\/title>\n<meta name=\"description\" content=\"Une attaque \u00e0 51 % menace un r\u00e9seau blockchain en prenant le contr\u00f4le 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