{"data":{"id":"924fd451-276b-4f10-9cb2-3b1c10f033f1","title":"Beyond public access in LLM pre-training data","summary":"Researchers tested whether OpenAI models recognise non-public, pay-walled books they were not licensed to train on, using the DE-COP membership inference attack on 34 copyrighted O'Reilly Media books (13,962 paragraphs). GPT-4o scored an AUROC of 0.82 (95% bootstrapped CI: 0.60 to 0.96), while GPT-3.5 Turbo and GPT-4o Mini scored near chance at 0.54 and 0.56. The authors caution that results are preliminary given the small book sample and differences across models.","solution":"N/A -- no mitigation discussed in source.","labels":["privacy","research"],"sourceUrl":"https://doi.org/10.1007/s43681-026-01438-z","publishedAt":"2026-10-30T00:00:00.000Z","cveId":null,"cweIds":null,"cvssScore":null,"cvssSeverity":null,"severity":"info","attackType":["membership_inference"],"issueType":"research","affectedPackages":null,"affectedPackageNames":null,"affectedPackageRefs":null,"affectedVendors":["OpenAI"],"affectedVendorsRaw":["OpenAI","GPT-4o","GPT-3.5 Turbo","GPT-4o Mini","Gemma","Qwen"],"classifierModel":"claude-haiku-5-5","classifierPromptVersion":"v4","summaryPromptVersion":"v2","headline":null,"headlinePromptVersion":null,"cvssVector":null,"attackVector":null,"attackComplexity":null,"privilegesRequired":null,"userInteraction":null,"exploitMaturity":null,"epssScore":null,"epssCheckedAt":null,"kevDateAdded":null,"advisoryAliases":null,"affectedPackagesSource":null,"affectedPackagesCheckedAt":null,"patchAvailable":null,"disclosureDate":"2026-10-30T00:00:00.000Z","fixReleasedAt":null,"daysToFix":null,"fixCheckedAt":null,"capecIds":null,"crossRefCount":0,"attackSophistication":"moderate","impactType":["confidentiality"],"aiComponentTargeted":"training_data","llmSpecific":true,"classifierConfidence":0.93,"researchCategory":"peer_reviewed","atlasIds":["AML.T0024.000"]}}