CVE-2026-122096

Uncontrolled Resource Consumption vulnerability in the sketch deserialization of Apache DataSketches Java. Several deserializers trusted sizes and counts declared in the serialized input. A small crafted input could make an application allocate an excessive amount of memory, leading to an OutOfMemoryError. A crafted string passed to FrequentLongsSketch.getInstance(String) could also make deserialization, or a later update, loop indefinitely. Only applications that deserialize sketches from untrusted sources are affected. This issue affects Apache DataSketches Java: through 9.0.0. Users are recommended to upgrade to version 9.1.0, which fixes the issue.