CVE-2026-44302: Snappier Snappier Has An Infinite Loop Vulnerability

HIGH
Advisory Identifier: GHSA-pggp-6c3x-2xmx
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CVSS 7.5
CWE-835
Published
Advisory Summary

CVE-2026-44302 is a HIGH (CVSS 7.5) snappier has an infinite loop vulnerability (CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')) affecting Snappier libraries in the NuGet ecosystem. The issue involves snappier has an infinite loop during snappystream decompression with malformed framed input. Remediation is available by upgrading affected packages to version 1.3.1.

CVE-2026-44302 at a Glance

CVE Identifier CVE-2026-44302
GHSA Identifier GHSA-pggp-6c3x-2xmx
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')
Affected Product Snappier
Package Ecosystem NuGet
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2026-44302

To remediate this vulnerability, upgrade all affected Snappier dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Snappier fixed: 1.3.1 
Upgrade Snappier to 1.3.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for Snappier

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-44302, inspect your project dependencies for Snappier:

inspect dependencies for Snappier

Analyze the terminal output to locate any version of Snappier in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.3.1), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop'), where the product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. In Snappier, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary `Snappier.SnappyStream` enters an uncatchable infinite loop when decompressing a malformed framed-format Snappy stream as small as 15 bytes. ### Details The hang manifests as a userspace busy loop with SnappyStreamDecompressor.Decompress repeatedly calling Crc32CAlgorithm.Append. The exact non-terminating loop in or above Decompress has not been traced further. ### PoC ```csharp 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 ``` ### Impact A caller using `SnappyStream` on attacker-controlled bytes can be made to spin forever and burn a thread until the process is killed. `try/catch` around the stream operation can't recover (no exception is thrown).

CVE-2026-44302 Affected Snappier Versions

1 component(s)
Fixed Versions:
1.3.1
Product / Package Ecosystem Affected Versions Fixed Version
Snappier
nuget/Snappier
NuGet
< 1.3.1
1.3.1

References

GitHub Advisory / Wiki ADVISORY
https://github.com/brantburnett/Snappier/security/advisories/GHSA-pggp-6c3x-2xmx
NVD — CVE-2026-44302 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-44302
Snappier Source Repository REPOSITORY
https://github.com/brantburnett/Snappier

Frequently Asked Questions

What is CVE-2026-44302?
CVE-2026-44302 is a security vulnerability in Snappier involving Snappier has an infinite loop during SnappyStream decompression with malformed framed input under CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop').
Which Snappier versions are affected?
Affected versions include releases prior to 1.3.1 across affected packages: Snappier.
What version fixes CVE-2026-44302?
Upgrading to 1.3.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is Snappier affected?
Yes, Snappier is affected in releases prior to 1.3.1. Upgrade your dependency to 1.3.1 or later.
What is the CVSS score of CVE-2026-44302?
CVE-2026-44302 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2026-44302?
CVE-2026-44302 is classified under CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop') (The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.).
How can I check NuGet dependencies for CVE-2026-44302?
Run the dependency tree command: 'inspect dependencies for Snappier'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-pggp-6c3x-2xmx",
  "modified" : "2026-05-13T16:41:52Z",
  "published" : "2026-05-06T20:53:23Z",
  "aliases" : [ "CVE-2026-44302" ],
  "summary" : "Snappier has an infinite loop during SnappyStream decompression with malformed framed input",
  "details" : "### Summary\n`Snappier.SnappyStream` enters an uncatchable infinite loop when decompressing a malformed framed-format Snappy stream as small as 15 bytes.\n\n### Details\nThe hang manifests as a userspace busy loop with SnappyStreamDecompressor.Decompress repeatedly calling Crc32CAlgorithm.Append. The exact non-terminating loop in or above Decompress has not been traced further.\n\n### PoC\n```csharp\nusing System.IO.Compression;\nusing Snappier;\n\nbyte[] data = { 0x00, 0x04, 0x00, 0x00, 0x64, 0x4e, 0x6c, 0x71, 0x79, 0x20, 0x77, 0x6f, 0x72, 0x6c, 0x64 };\nusing var src = new MemoryStream(data);\nusing var snap = new SnappyStream(src, CompressionMode.Decompress);\nusing var dst = new MemoryStream();\nsnap.CopyTo(dst);   // never returns\n```\n\n### Impact\nA caller using `SnappyStream` on attacker-controlled bytes can be made to spin forever and burn a thread until the process is killed. `try/catch` around the stream operation can't recover (no exception is thrown).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "NuGet",
      "name" : "Snappier"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.3.1"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.3.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/brantburnett/Snappier/security/advisories/GHSA-pggp-6c3x-2xmx"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-44302"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/brantburnett/Snappier"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-835" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-06T20:53:23Z",
    "nvd_published_at" : "2026-05-12T22:16:36Z"
  }
}