{"id":96114,"date":"2026-04-12T13:49:54","date_gmt":"2026-04-12T10:49:54","guid":{"rendered":"https:\/\/forklog.com\/en\/?p=96114"},"modified":"2026-04-12T13:50:15","modified_gmt":"2026-04-12T10:50:15","slug":"zero-day-flaw-discovered-in-bitcoin-mining-mechanism","status":"publish","type":"post","link":"https:\/\/forklog.com\/en\/zero-day-flaw-discovered-in-bitcoin-mining-mechanism\/","title":{"rendered":"Zero-Day Flaw Discovered in Bitcoin Mining Mechanism"},"content":{"rendered":"<p>Since its inception, a computational error has existed in Bitcoin&#8217;s mining algorithm, allowing blocks to be mined at an exceptionally high speed. This was revealed by researcher Lo\u00efc Morel.<\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"fr\" dir=\"ltr\">Satoshi s&#8217;est tromp\u00e9.<\/p>\n<p>Il y a un bug dans le minage de Bitcoin depuis le tout premier jour. C&#8217;est une simple erreur de calcul de Satoshi qui pourrait \u00eatre exploit\u00e9e pour miner des blocs \u00e0 une vitesse d\u00e9lirante. C&#8217;est un des bugs que le BIP-0054 (en discussion) r\u00e9sout. Je vous\u2026 <a href=\"https:\/\/t.co\/GurNv3qKrZ\">pic.twitter.com\/GurNv3qKrZ<\/a><\/p>\n<p>\u2014 Lo\u00efc Morel (@Loic_Pandul) <a href=\"https:\/\/twitter.com\/Loic_Pandul\/status\/2042880037330858154?ref_src=twsrc%5Etfw\">April 11, 2026<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<p>According to the publication, the flaw is related to the <a href=\"https:\/\/forklog.com\/en\/news\/what-are-hashrate-and-mining-difficulty-in-cryptocurrencies\">difficulty adjustment<\/a> mechanism.<\/p>\n<p>Every 2016 blocks (approximately every two weeks), nodes recalculate the target to ensure a block is mined every 10 minutes, regardless of miners&#8217; computational power. For this adjustment, nodes measure the duration of the last period, compare it to the target value (2016 x 600 = 1,209,600 seconds), and adjust the difficulty accordingly.<\/p>\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>&#8220;The error lies in these calculations. To measure the timing of blocks in the past period, a node compares the timestamp of the first block of the period with the timestamp of the last. Instinctively, this seems logical, but it is actually a mistake because there are only 2015 intervals between the first and last blocks of the period, not 2016,&#8221; Morel explained.<\/p>\n<\/blockquote>\n<p>If t0 is the timestamp of the first block and t2015 is the timestamp of the last, the node calculates the elapsed time as T = t2015 \u2014 t0. This results in 2015 intervals (from t0 to t1 > from t1 to t2 > \u2026 > from t2014 to t2015).<\/p>\n<p>To achieve 2016 intervals, a different formula is needed: T = t2015 \u2014 t-1, where t-1 is the timestamp of the last block of the previous period.<\/p>\n<p>This is known as an &#8220;off-by-one&#8221; error. This bug introduces an error of approximately 0.05% towards slightly increased difficulty.<\/p>\n<p>However, the real issue lies elsewhere. The flaw results in non-overlapping adjustment periods\u2014the timestamp of the last block of one period is not considered in the calculation of the next.<\/p>\n<h2 class=\"wp-block-heading\">Time Manipulation<\/h2>\n<p>This gap enables a &#8220;time warp&#8221; attack. Its principle is as follows:<\/p>\n<ol class=\"wp-block-list\">\n<li>A miner controlling a significant portion of computational power begins setting the minimum allowable timestamps for all blocks in the period (except the last).<\/li>\n<li>In the last block of the period, they artificially assign the maximum allowable timestamp.<\/li>\n<li>After the period ends, the difficulty is adjusted. Due to the attacker&#8217;s manipulation of timestamps, the measured period appears longer than it actually was, resulting in reduced difficulty.<\/li>\n<li>The attacker repeats a similar manipulation in the next period. Since periods do not overlap, the first block of the second attack period can have a timestamp from the distant past, while the previous block has a future timestamp. This gap increases from period to period.<\/li>\n<\/ol>\n<p>By repeating the process several times, an attacker could theoretically reduce mining difficulty to a level where up to six blocks are created per second (instead of one every 10 minutes).<\/p>\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>&#8220;The consequences would be dire: time locks become useless, the network is overloaded, the number of reorganizations increases, and transaction confirmations lose value. This would allow the attacker to collect block rewards at a frantic pace,&#8221; the researcher added.<\/p>\n<\/blockquote>\n<p>The attack would be impossible if the first and last blocks of two consecutive periods coincided.<\/p>\n<h2 class=\"wp-block-heading\">How to Fix This Error?<\/h2>\n<p>Morel noted that the issue can be addressed through a soft fork under <a href=\"https:\/\/github.com\/bitcoin\/bips\/blob\/master\/bip-0054.md\">BIP-0054<\/a>.<\/p>\n<p>The initiative proposes that the first block of a new difficulty period has a timestamp no more than two hours beyond the timestamp of the last block of the previous period.<\/p>\n<p>This restriction restores &#8220;some form of continuity&#8221; between periods, prevents manipulation of time intervals, and renders the &#8220;time warp&#8221; attack unfeasible.<\/p>\n<p>Back in February, Castle Island Ventures partner Nic Carter <a href=\"https:\/\/forklog.com\/en\/news\/expert-predicts-bitcoins-corporate-takeover-due-to-quantum-threat\">predicted<\/a> a &#8220;corporate takeover&#8221; of Bitcoin due to the quantum threat.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Since its inception, a computational error has existed in Bitcoin&#8217;s mining algorithm, allowing blocks to be mined at an exceptionally high speed.<\/p>\n","protected":false},"author":1,"featured_media":96115,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"select":"1","news_style_id":"1","cryptorium_level":"","_short_excerpt_text":"Computational error in Bitcoin mining allowed high-speed block creation since inception.","creation_source":"","_metatest_mainpost_news_update":false,"footnotes":""},"categories":[3],"tags":[18,25,1301],"class_list":["post-96114","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news-and-analysis","tag-bitcoin","tag-blockchain","tag-blockchain-vulnerabilities"],"aioseo_notices":[],"amp_enabled":true,"views":"42","promo_type":"1","layout_type":"1","short_excerpt":"Computational error in Bitcoin mining allowed high-speed block creation since inception.","is_update":"","_links":{"self":[{"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/posts\/96114","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/comments?post=96114"}],"version-history":[{"count":1,"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/posts\/96114\/revisions"}],"predecessor-version":[{"id":96116,"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/posts\/96114\/revisions\/96116"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/media\/96115"}],"wp:attachment":[{"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/media?parent=96114"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/categories?post=96114"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/forklog.com\/en\/wp-json\/wp\/v2\/tags?post=96114"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}