CVE-2026-42241Network attack vector

Service interruption via oversized decimal stack allocation

Published May 7, 2026 · Updated May 7, 2026

Stack exhaustion in G-Research ParquetSharp 18.1.0 through 23.0.0 allows remote attackers to interrupt a service via a crafted Parquet file. DecimalConverter.ReadDecimal uses the decimal column width directly for stack allocation without first imposing a safe limit, so an unreasonable width exhausts the thread stack. Reachability requires an application to read untrusted Parquet files, and exploitation interrupts that application or its hosting service.

CVSS severity5.3
Medium
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stack exhaustion in G-Research ParquetSharp 18.1.0 through 23.0.0 allows remote attackers to interrupt a service via a crafted Parquet file. DecimalConverter.ReadDecimal uses the decimal column width directly for stack allocation without first imposing a safe limit, so an unreasonable width exhausts the thread stack. Reachability requires an application to read untrusted Parquet files, and exploitation interrupts that application or its hosting service.

The record

CVE
CVE-2026-42241
Published
May 7, 2026
Updated
May 7, 2026
Vendor
G-Research
Product
ParquetSharp
Classifications
CWE-789, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 7, 2026CVE publishedPublication date reported by the CVE source.
  2. May 7, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 18.1.0, < 23.0.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

G-Research · ParquetSharpversion=>= 18.1.0, < 23.0.0.1

Published CVSS scores

5.3G-ResearchCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-789Memory Allocation with Excessive Size Value
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo