Gửi #945051: tdunning t-digest 3.3 Unvalidated NaN Centroid Means Cause Quadratic Blowupthông tin

tiêu đềtdunning t-digest 3.3 Unvalidated NaN Centroid Means Cause Quadratic Blowup
Mô tảWhile 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.
Nguồn⚠️ https://github.com/tdunning/t-digest/issues/229
Người dùng
 Yu_Bao from PayPal Cyber Security Team (UID 100783)
Đệ trình24/08/2026 18:41 (cách đây 2 các tháng)
Kiểm duyệt19/09/2026 19:04 (26 days later)
Trạng tháiBản sao
Mục VulDB401776 [tdunning t-digest đến 3.3 MergingDigest.fromBytes nâng cao đặc quyền]
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