Enviar #945051: tdunning t-digest 3.3 Unvalidated NaN Centroid Means Cause Quadratic Blowupinformación

Títulotdunning t-digest 3.3 Unvalidated NaN Centroid Means Cause Quadratic Blowup
DescripciónWhile 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.
Fuente⚠️ https://github.com/tdunning/t-digest/issues/229
Usuario
 Yu_Bao from PayPal Cyber Security Team (UID 100783)
Sumisión2026-08-24 18:41 (hace 2 meses)
Moderación2026-09-19 19:04 (26 days later)
EstadoDuplicado
Entrada de VulDB401776 [tdunning t-digest hasta 3.3 MergingDigest.fromBytes escalada de privilegios]
Puntos0

Do you know our Splunk app?

Download it now for free!