--- title: The Duty of a Scholar | daily.dev description: Colin Percival recounts discovering in 2004 that Intel's Hyper-Threading could leak RSA private key bits via cache state, letting him reconstruct an entire key... canonical: https://daily.dev/posts/the-duty-of-a-scholar-zdzziuj7y twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: The Duty of a Scholar | daily.dev og:description: Colin Percival recounts discovering in 2004 that Intel's Hyper-Threading could leak RSA private key bits via cache state, letting him reconstruct an entire key... og:url: https://daily.dev/posts/the-duty-of-a-scholar-zdzziuj7y og:image: https://api.daily.dev/og/posts/zDZZIuJ7y.png og:image:alt: The Duty of a Scholar 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. # The Duty of a Scholar **[Hacker News](https://daily.dev/sources/hn)** · 9 min read · 0 upvotes · 0 comments ## Summary Colin Percival recounts discovering in 2004 that Intel's Hyper-Threading could leak RSA private key bits via cache state, letting him reconstruct an entire key from a proof-of-concept exploit by mid-December. He spent six months quietly coordinating disclosure, delaying his Oxford thesis work, before presenting the findings at BSDCan on May 13, 2005. Intel reportedly pressured Yahoo to have him withdraw the paper, but Yahoo noted he wasn't their employee. Advisories followed from FreeBSD, NetBSD, Red Hat, SCO, and Ubuntu. He also describes reporting an Amazon EC2 firewall bug in 2009 and later publishing advice to customers in 2012 after Amazon failed to act, framing both cases as part of a broader ethical duty for scholars to actively share knowledge. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How did the Hyper-Threading side-channel vulnerability leak RSA private key data? Intel's Hyper-Threading, introduced in 2002, allowed information to leak between execution threads through shared cache state. A researcher built a proof-of-concept exploit by mid-December 2004 that stole enough bits of an RSA private key to reconstruct the entire key, then spent about six months coordinating disclosure before publishing an advisory and presenting findings at BSDCan on May 13, 2005. _Developers tracking CPU-level security flaws can follow coordinated disclosure case studies like this on daily.dev._ ### Which vendors released advisories for the 2005 Hyper-Threading cache side-channel vulnerability? FreeBSD, NetBSD, Red Hat, SCO, and Ubuntu published advisories at the same time or soon after the researcher's own advisory and BSDCan presentation on May 13, 2005. The disclosure process took about six months from proof-of-concept to public release, which the researcher notes was unusually long for a coordinated disclosure. _Anyone weighing how long a coordinated disclosure should take can compare real timelines like this on daily.dev._ ### What happened when Intel tried to stop publication of the Hyper-Threading security research? Intel, irritated by the impending publication, asked Yahoo to order the researcher to withdraw the paper. Yahoo replied that, unlike many FreeBSD developers at the time, the researcher was not actually employed by them and so they had no leverage to threaten his job, and the paper was presented at BSDCan as planned on May 13, 2005. _Security researchers navigating vendor pressure during disclosure can find similar firsthand accounts on daily.dev._ ## Community take How the wider developer community reacted, aggregated from 1 discussion and 32 comments across hackernews (as of 2026-11-01). **TL;DR:** Discussion centers less on the cache-timing disclosure itself and more on tangents: whether academia still embodies 'scholarship,' a sharp factual dispute over a US healthcare claim in the post, and skepticism about whether Intel's dismissal of the vulnerability still holds today. **Sentiment:** 30% positive · 45% mixed · 25% skeptical **The case for** - Some praise the author for holding himself to an ethical standard of disclosure that most professionals (including IEEE members) don't actually practice. - The historical exchange with Intel is seen as an early, vindicated instance of a timing-exploit warning that proved practical (e.g. via Chrome). **The pushback** - Several argue modern academia is driven by incremental publishing for tenure/grants rather than genuine scholarship. - A detailed pushback claims the post's statement about needing US employment/insurance for healthcare is factually wrong given Medicaid eligibility, with the author disputing the specifics. - One commenter argues some academic disciplines now prioritize activism over knowledge production, which others reject as uncharitable. **By community** - hackernews (heated): The thread splits between abstract arguments over the state of academia and a contentious, detailed dispute over a healthcare/Medicaid claim in the post, with the author actively defending himself in comments. **Hottest debate:** Whether the author's claim about needing US employment/insurance for healthcare in 2005 was factually accurate, given Medicaid eligibility rules. **Open questions** - Did Medicaid eligibility in 2005 actually cover someone in the author's situation, as disputed in the thread? - Are timing/cache-based exploits like the one described still dismissed as 'impractical' by vendors today, given modern attack techniques? **Highlights** > Are you aware of a program down south called Medicaid? In my state it covers anyone making below $1,799/mo, with no asset test. The details do vary, that's for adults without dependent children or disabilities. I believe you were unemployed at the time? I mention because: > Had I been living in the USA, I would have needed to prioritize seeking employment and medical insurance and likely would not have been able to discharge the duty which fate had thrust upon me. Normally I just shrug this kind of cheap dig off. Most people don't care about what's true, and that just has to be accepted. But surely the duty of a scholar includes a duty to the truth? I know you would prefer to keep that bit, since I'm certain it correctly reflects your rating of our country's respective approaches to health care. But it isn't true. Is the thing. > — [samatman on hackernews · 1 comments](https://news.ycombinator.com/item?id=50321160) > By revealed preference, modern academia is about churning incremental papers in order to obtain tenure and research grants. > — [cperciva on hackernews · 2 comments](https://news.ycombinator.com/item?id=50320597) > Does "opening a malicious web site in Chrome" count as "controlled conditions"? > — [cperciva on hackernews](https://news.ycombinator.com/item?id=50320941) > > Members of the IEEE commit, for example, "to hold paramount the safety, health, and welfare of the public..." without that duty being limited to hazards arising from projects employing the Engineer in question: The duty "to disclose promptly" vests in any Engineer who recognizes that the hazard exists. As an active member of the IEEE for over a decade now, I have never seen anyone (aside from the author here) take this duty seriously. There are plenty of IEEE members working on things that directly cause such hazards. > — [ballmerpoint on hackernews](https://news.ycombinator.com/item?id=50320150) > This took place in 2005, nearly a decade before Medicaid expansion went into effect. > — [ameliaquining on hackernews](https://news.ycombinator.com/item?id=50322515) **Source threads** - [hackernews](https://news.ycombinator.com/item?id=50319061) · 98 points · 32 comments ## Similar posts on daily.dev - [Key Leaks, Vault Failures, and TEE Attacks: Highlights from RWC 2026](https://daily.dev/posts/key-leaks-vault-failures-and-tee-attacks-highlights-from-rwc-2026-xmn8ihmum) · GitGuardian · 0 upvotes · 0 comments - [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 - [20 Years on AWS and Never Not My Job](https://daily.dev/posts/20-years-on-aws-and-never-not-my-job-t0ueepmhw) · Hacker News · 3 upvotes · 0 comments - [Schneier on Security](https://daily.dev/posts/schneier-on-security-t9mhsyxfa) · Schneier on Security · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#ethics](https://daily.dev/tags/ethics) [View this post on daily.dev](https://daily.dev/posts/the-duty-of-a-scholar-zdzziuj7y) ```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":"The Duty of a Scholar","url":"https://daily.dev/posts/the-duty-of-a-scholar-zdzziuj7y","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/the-duty-of-a-scholar-zdzziuj7y"},"datePublished":"2026-10-31T20:20:12.302Z","dateModified":"2026-11-01T04:21:16.407Z","description":"Colin Percival recounts discovering in 2004 that Intel's Hyper-Threading could leak RSA private key bits via cache state, letting him reconstruct an entire key...","image":"https://media.daily.dev/image/upload/s--P4t4XyoV--/f_auto/v1722860399/public/Placeholder%2001","thumbnailUrl":"https://media.daily.dev/image/upload/s--P4t4XyoV--/f_auto/v1722860399/public/Placeholder%2001","isAccessibleForFree":true,"articleSection":"Hacker News","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Hacker News","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/hn","url":"https://daily.dev/sources/hn"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/the-duty-of-a-scholar-zdzziuj7y","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"security,ethics","timeRequired":"PT9M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Hacker News","item":"https://daily.dev/sources/hn"},{"@type":"ListItem","position":3,"name":"The Duty of a Scholar"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/the-duty-of-a-scholar-zdzziuj7y#faq","mainEntity":[{"@type":"Question","name":"How did the Hyper-Threading side-channel vulnerability leak RSA private key data?","acceptedAnswer":{"@type":"Answer","text":"Intel's Hyper-Threading, introduced in 2002, allowed information to leak between execution threads through shared cache state. 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