--- title: RCE As a Feature | daily.dev description: A former curriculum writer at an ed-tech company recounts discovering severe security vulnerabilities in a C-interpreter product used by K-12 schools. A... canonical: https://daily.dev/posts/rce-as-a-feature-xeeuukhv1 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: RCE As a Feature | daily.dev og:description: A former curriculum writer at an ed-tech company recounts discovering severe security vulnerabilities in a C-interpreter product used by K-12 schools. A... og:url: https://daily.dev/posts/rce-as-a-feature-xeeuukhv1 og:image: https://api.daily.dev/og/posts/xEEuUKHv1.png og:image:alt: RCE As a Feature 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. # RCE As a Feature **[The Daily WTF](https://daily.dev/sources/thedailywtf)** · 4 min read · 0 upvotes · 0 comments ## Summary A former curriculum writer at an ed-tech company recounts discovering severe security vulnerabilities in a C-interpreter product used by K-12 schools. A locally-installed daemon ran an unauthenticated websocket server bound to 0.0.0.0 that accepted arbitrary C code for execution, enabling remote code execution from any website or any device on the same network. The company also had a server-side eval() code injection exposing plaintext credit card data, plus a default-credential router. The founder patched some issues quietly without notifying schools, and the company remains in business and has been recognized in an industry ranking. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What made the ed-tech company's 'Run Locally' C interpreter feature vulnerable to remote code execution? A locally installed daemon ran an unauthenticated websocket server on startup, exposing an endpoint at localhost:12345/execute_c_program that accepted arbitrary C code as a string parameter and executed it via the interpreter, including calls like execv(). Since there was no authentication, any website could trigger execution simply by getting a user to visit it, and the server was also bound to 0.0.0.0, exposing it to the entire local network. _Reviewing how local helper daemons expose network ports is easier when developers track real-world exploit writeups like this on daily.dev._ ### Why is binding a local server to 0.0.0.0 instead of 127.0.0.1 dangerous? Binding to 0.0.0.0 makes a service reachable from any device on the same network, not just the local machine. In the ed-tech interpreter case, this meant any computer on a school's network could send arbitrary C code to another machine's execution endpoint without any authentication, turning a local convenience feature into a network-wide remote code execution vector. _Developers hardening local services against network exposure can follow real vulnerability breakdowns like this on daily.dev._ ## Similar posts on daily.dev - [Unauthenticated Remote Code Execution in OpenCode](https://daily.dev/posts/unauthenticated-remote-code-execution-in-opencode-cxvxefhzp) · Hacker News · 2 upvotes · 0 comments - [CISA orders urgent action on actively exploited Langflow RCE flaw](https://daily.dev/posts/cisa-orders-urgent-action-on-actively-exploited-langflow-rce-flaw-jioynjbkx) · BleepingComputer · 0 upvotes · 0 comments - [Langflow RCE under active attack months after a patch was shipped](https://daily.dev/posts/langflow-rce-under-active-attack-months-after-a-patch-was-shipped-jzjannqnb) · CSO Online · 0 upvotes · 0 comments - [A security checklist for your React and Next.js apps](https://daily.dev/posts/a-security-checklist-for-your-react-and-next-js-apps-pevwqmgpr) · The New Stack · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#authentication](https://daily.dev/tags/authentication), [#c](https://daily.dev/tags/c), [#edtech](https://daily.dev/tags/edtech) [View this post on daily.dev](https://daily.dev/posts/rce-as-a-feature-xeeuukhv1) ```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":"RCE As a Feature","url":"https://daily.dev/posts/rce-as-a-feature-xeeuukhv1","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/rce-as-a-feature-xeeuukhv1"},"datePublished":"2026-08-24T11:06:35.768Z","dateModified":"2026-09-14T08:50:51.456Z","description":"A former curriculum writer at an ed-tech company recounts discovering severe security vulnerabilities in a C-interpreter product used by K-12 schools. 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