{"paper_id":"48b0d8d5-5239-4c3e-9f2d-25b0525318c5","body_text":"Cyber Threat Hunting by Finetuning LLM for DDoS Detection | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Cyber Threat Hunting by Finetuning LLM for DDoS Detection Abdul Hannan Chougle, Ronak Ajwani, Shreya Chhatwani, Manit Khira, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7225835/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Cybersecurity threats, particularly Distributed Denial-of-Service (DDoS) attacks, pose significant risks to modern network infras- tructures. Traditional detection mechanisms often struggle with scalability and adaptability, necessitating more advanced AI-driven solutions. This research initially explored zero-shot prompting with Large Language Models (LLMs) for cyber threat detection; however, the results highlighted the limitations of general-purpose models in handling domain-specific classification tasks.To improve detection performance, we adopted a supervised fine-tuning approach, using the CICIDS 2019 dataset. Four state-of-the-art LLMs—Llama 3.1, Llama 3.2, Mistral —were fine-tuned using Low-Rank Adaptation (LoRA) to optimize classification performance while maintaining computational efficiency. The models were evaluated on key performance metrics, including accuracy, precision, recall, F1 score, and latency, with Llama 3.2 showing the highest accuracy and the most balanced trade-offs. Structured prompt engineering further enhanced the effectiveness of fine-tuned models in identifying network threats.The findings underscore the potential of supervised fine-tuning for adapting LLMs to cybersecurity domains, offering a scalable and robust solution for real-time intrusion detection. Future work may focus on deployment strategies and integration with multimodal threat intelligence to enhance practical applicability. LLM Fine-Tuning Open-Source LLMs Prompt Engineering LLaMA Mistral Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-7225835\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":true,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":508162156,\"identity\":\"1f22d586-fb22-4575-9a6c-2666f63596fe\",\"order_by\":0,\"name\":\"Abdul Hannan Chougle\",\"email\":\"data:image/png;base64,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\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Abdul\",\"middleName\":\"Hannan\",\"lastName\":\"Chougle\",\"suffix\":\"\"},{\"id\":508162157,\"identity\":\"1dc97aec-c03f-4937-aff5-8e6ac7d50c0f\",\"order_by\":1,\"name\":\"Ronak Ajwani\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Ronak\",\"middleName\":\"\",\"lastName\":\"Ajwani\",\"suffix\":\"\"},{\"id\":508162158,\"identity\":\"1739ee59-e69f-45e9-84ed-d458fe89006a\",\"order_by\":2,\"name\":\"Shreya Chhatwani\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Shreya\",\"middleName\":\"\",\"lastName\":\"Chhatwani\",\"suffix\":\"\"},{\"id\":508162159,\"identity\":\"6de571ed-9a38-4ccc-ad3e-39b07546352c\",\"order_by\":3,\"name\":\"Manit Khira\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Manit\",\"middleName\":\"\",\"lastName\":\"Khira\",\"suffix\":\"\"},{\"id\":508162160,\"identity\":\"5b863d15-03a4-4614-8c53-5595b28021be\",\"order_by\":4,\"name\":\"Dr. Nupur Giri\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"Dr.\",\"firstName\":\"Nupur\",\"middleName\":\"\",\"lastName\":\"Giri\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2025-07-27 11:08:22\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-7225835/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-7225835/v1\",\"draftVersion\":[],\"editorialEvents\":[],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":95604445,\"identity\":\"72d7d059-9ea5-44e1-9c0b-a297d1ca972c\",\"added_by\":\"auto\",\"created_at\":\"2025-11-11 06:39:13\",\"extension\":\"pdf\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":626620,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"Manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7225835/v1_covered_2c4d44a8-17f0-4cbf-b21d-9f1c43bf1d9c.pdf\"}],\"financialInterests\":\"No competing interests reported.\",\"formattedTitle\":\"Cyber Threat Hunting by Finetuning LLM for DDoS Detection\",\"fulltext\":[],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":false,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":true,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":false,\"isAuthorSuppliedPdf\":true,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":true,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"researchsquare\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":true,\"externalIdentity\":\"\",\"sideBox\":\"\",\"snPcode\":\"\",\"submissionUrl\":\"/submission\",\"title\":\"Research Square\",\"twitterHandle\":\"researchsquare\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"\",\"reportingPortfolio\":\"\",\"inReviewEnabled\":false,\"inReviewRevisionsEnabled\":true},\"keywords\":\"LLM Fine-Tuning, Open-Source LLMs, Prompt Engineering, LLaMA, Mistral\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-7225835/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-7225835/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003eCybersecurity threats, particularly Distributed Denial-of-Service (DDoS) attacks, pose significant risks to modern network infras- tructures. 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