{"data":{"id":"862aa7f7-5d07-4a6c-88d5-d735f249190f","title":"Token-Level Attribution of Multi-Mode LLM Watermarks: Optimal Rule and Belief Weighting","summary":"Researchers study token-level attribution for multi-mode Gumbel-max LLM watermarks, where a document may mix spans watermarked under different secret keys with unwatermarked text. They show that the optimal rule reports the mode with the largest prior-weighted alternative density and rejects when this density exceeds a common threshold, then propose the BLADE detector, which keeps the exact Type I error and attains higher correct-label power than compared detectors on OPT-1.3B and other open-weight models.","solution":"N/A -- no mitigation discussed in source.","labels":["security","research"],"sourceUrl":"https://arxiv.org/abs/2610.23601v1","publishedAt":"2026-10-16T15:18:28.000Z","cveId":null,"cweIds":null,"cvssScore":null,"cvssSeverity":null,"severity":"info","attackType":[],"issueType":"research","affectedPackages":null,"affectedPackageNames":null,"affectedPackageRefs":null,"affectedVendors":[],"affectedVendorsRaw":["OPT-1.3B"],"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":"2026-10-16T15:18:28.000Z","capecIds":null,"crossRefCount":0,"attackSophistication":"advanced","impactType":["integrity"],"aiComponentTargeted":"model","llmSpecific":true,"classifierConfidence":0.9,"researchCategory":"preprint","atlasIds":null}}