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CVE-2026-103634 affects Count-Min sketch deserialization in Apache DataSketches C++ versions 4.1.0 through 5.2.0, inclusive. The count_min_sketch::deserialize() function omits the preamble from its input-size check, allowing truncated input to trigger reads up to 16 bytes beyond the input buffer. Separately, table-size calculations use 32-bit arithmetic on serialized bucket and hash-function counts. Crafted values can overflow the calculation to zero, producing a sketch with an empty table. Subsequent updates or estimate queries can then access memory outside the heap allocation. Only applications deserializing Count-Min sketches from untrusted sources are affected.
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Cross-references every affected SKU, including bundled OEM variants.
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