| 제목 | tdunning t-digest 3.3 Unvalidated NaN Centroid Means Cause Quadratic Blowup |
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| 설명 | While digging further into MergingDigest.fromBytes() past the array-bounds issue I already reported, I noticed it also skips the one check every other write path in this class enforces: rejecting NaN means. MergingDigest.add(double, int) throws on NaN, and even the sibling AVLTreeDigest.fromBytes() routes through add() so it inherits that check for free — but MergingDigest.fromBytes() writes straight into the backing arrays and never calls add(), so a digest can be deserialized with an arbitrary number of NaN means baked in. The very next merge of that digest — a single add(x, w) call, exactly what a real aggregator does with each new raw value — hands those NaNs to Sort.quickSort(), whose median-of-three pivot logic silently degrades from O(n log n) to O(n²) once comparisons stop forming a total order. |
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| 원천 | ⚠️ https://github.com/tdunning/t-digest/issues/229 |
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| 사용자 | Yu_Bao from PayPal Cyber Security Team (UID 100783) |
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| 제출 | 2026. 08. 24. PM 06:41 (2 개월 ago) |
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| 모더레이션 | 2026. 09. 19. PM 07:04 (26 days later) |
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| 상태 | 중복 |
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| VulDB 항목 | 401776 [tdunning t-digest 까지 3.3 MergingDigest.fromBytes 권한 상승] |
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| 포인트들 | 0 |
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