--- title: MIT boffins' TONTOU attack slips through Spectre... description: MIT researchers have developed a new attack called TONTOU that bypasses existing Spectre mitigations on Intel and AMD CPUs. The attack exploits timer... canonical: https://daily.dev/posts/mit-boffins-tontou-attack-slips-through-spectre-defenses-on-intel-and-amd-cpus-vaofpeqkx twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: MIT boffins' TONTOU attack slips through Spectre defenses on Intel and AMD CPUs | daily.dev og:description: MIT researchers have developed a new attack called TONTOU that bypasses existing Spectre mitigations on Intel and AMD CPUs. The attack exploits timer... og:url: https://daily.dev/posts/mit-boffins-tontou-attack-slips-through-spectre-defenses-on-intel-and-amd-cpus-vaofpeqkx og:image: https://api.daily.dev/og/posts/vAOfpEQKx.png og:image:alt: MIT boffins' TONTOU attack slips through Spectre defenses on Intel and AMD CPUs og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # MIT boffins' TONTOU attack slips through Spectre defenses on Intel and AMD CPUs **[The Register](https://daily.dev/sources/theregister)** · 3 min read · 0 upvotes · 0 comments ## Summary MIT researchers have developed a new attack called TONTOU that bypasses existing Spectre mitigations on Intel and AMD CPUs. The attack exploits timer interrupts to reopen the branch predictor poisoning window, and includes a working proof-of-concept exploit targeting AMD Zen 2 processors. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the TONTOU attack and how does it bypass Spectre defenses on Intel and AMD CPUs? TONTOU is a CPU side-channel attack developed by MIT researchers that bypasses existing Spectre mitigations by exploiting timer interrupts to reopen the branch predictor poisoning window. Existing Spectre defenses fail to account for this interrupt-based vector. The researchers demonstrated a working exploit targeting AMD Zen 2 processors, proving the attack is practical and not merely theoretical. _Security engineers tracking CPU-level vulnerabilities like TONTOU follow hardware exploit disclosures on daily.dev._ ## Similar posts on daily.dev - [New type of attack can slip past the defenses in your computer’s processor](https://daily.dev/posts/new-type-of-attack-can-slip-past-the-defenses-in-your-computer-s-processor-hhyhhdxyi) · MIT News · 0 upvotes · 0 comments - [New Spectre v2 attack variant leaks Linux root password hash in minutes](https://daily.dev/posts/new-spectre-v2-attack-variant-leaks-linux-root-password-hash-in-minutes-l3pz2cusr) · BleepingComputer · 1 upvotes · 0 comments - [Newer RISC-V CPUs Vulnerable To Spectre V1 - Linux Mitigation Patches Posted](https://daily.dev/posts/newer-risc-v-cpus-vulnerable-to-spectre-v1---linux-mitigation-patches-posted-w75vepfxx) · Phoronix · 0 upvotes · 0 comments - [NDSS 2025 – CounterSEVeillance: Performance-Counter Attacks On AMD SEV-SNP](https://daily.dev/posts/ndss-2025-counterseveillance-performance-counter-attacks-on-amd-sev-snp-gqf73tije) · Security Boulevard · 1 upvotes · 0 comments --- Tags: [#intel](https://daily.dev/tags/intel), [#amd](https://daily.dev/tags/amd) [View this post on daily.dev](https://daily.dev/posts/mit-boffins-tontou-attack-slips-through-spectre-defenses-on-intel-and-amd-cpus-vaofpeqkx) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"MIT boffins' TONTOU attack slips through Spectre defenses on Intel and AMD CPUs","url":"https://daily.dev/posts/mit-boffins-tontou-attack-slips-through-spectre-defenses-on-intel-and-amd-cpus-vaofpeqkx","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/mit-boffins-tontou-attack-slips-through-spectre-defenses-on-intel-and-amd-cpus-vaofpeqkx"},"datePublished":"2026-08-07T14:17:56.257Z","dateModified":"2026-08-07T14:18:45.687Z","description":"MIT researchers have developed a new attack called TONTOU that bypasses existing Spectre mitigations on Intel and AMD CPUs. 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Existing Spectre defenses fail to account for this interrupt-based vector. The researchers demonstrated a working exploit targeting AMD Zen 2 processors, proving the attack is practical and not merely theoretical. Security engineers tracking CPU-level vulnerabilities like TONTOU follow hardware exploit disclosures on daily.dev."}}]} ```