CVE-2026-42241: G-Research Parquetsharp

Medium severity, CVSS 5.3. EPSS: 0.5% chance of exploitation in the next 30 days.

ParquetSharp is a .NET library for reading and writing Apache Parquet files. From version 18.1.0 to before version 23.0.0.1, DecimalConverter.ReadDecimal makes a stackalloc using what might be an attacker-supplied value. If an attacker declares a decimal column with some unreasonable width, this could lead to a stack overflow. In a service environment, this would potentially take down a service. This affects applications using ParquetSharp to read untrusted Parquet files in a network service. This issue has been patched in version 23.0.0.1.

Affected products

• G-Research Parquetsharp: from 18.1.0, before 23.0.0.1 (fixed in 23.0.0.1)

Published 2026-05-07. Last modified 2026-06-17.