CVE-2026-42448: Magic Wormhole Receive, With --output Pointing At Vulnerability

LOW
Advisory Identifier: GHSA-cf92-gfcw-6v53
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CVSS 3.5
CWE-22
Published
Advisory Summary

CVE-2026-42448 is a LOW (CVSS 3.5) receive, with --output pointing at vulnerability (CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')) affecting Magic Wormhole libraries in the PyPI ecosystem. The issue involves receive, with --output pointing at an existing directory can be path-traversed. Remediation is available by upgrading affected packages to version 0.24.0.

CVE-2026-42448 at a Glance

CVE Identifier CVE-2026-42448
GHSA Identifier GHSA-cf92-gfcw-6v53
Severity LOW
CVSS v3.1 Base Score 3.5
CWE Classification CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Affected Product Magic Wormhole
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 3.5

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

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

How to Fix CVE-2026-42448

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

magic-wormhole fixed: 0.24.0 
pip install magic-wormhole>=0.24.0
Verify Direct and Transitive Dependencies

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

pip show magic-wormhole

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-42448, inspect your installed packages using pip:

pip show magic-wormhole

Analyze the terminal output to locate any version of Magic Wormhole in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.24.0), your application is affected.

Note: The pip show magic-wormhole command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'), where the product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. In Magic Wormhole, 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

### Impact A receiver who specifies "--output <dir>" where that output directory currently exists (as a directory). ### Patches 0.24.0 will contain the patch ### Workarounds Ensure local target directories specified by "--output" do not already exist ### Resources Private email and Signal communications from a user. Magic Wormhole thanks @marduc812

CVE-2026-42448 Affected Magic Wormhole Versions

1 component(s)
Fixed Versions:
0.24.0
Product / Package Ecosystem Affected Versions Fixed Version
magic-wormhole
pypi/magic-wormhole
PyPI
< 0.24.0
≥ 0.23.0
All 1 versions
0.23.0
0.24.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/magic-wormhole/magic-wormhole/security/advisories/GHSA-cf92-gfcw-6v53
NVD — CVE-2026-42448 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42448
Magic Wormhole Source Repository REPOSITORY
https://github.com/magic-wormhole/magic-wormhole

Frequently Asked Questions

What is CVE-2026-42448?
CVE-2026-42448 is a security vulnerability in Magic Wormhole involving receive, with --output pointing at an existing directory can be path-traversed under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
Which Magic Wormhole versions are affected?
Affected versions include releases prior to 0.24.0 across affected packages: magic-wormhole.
What version fixes CVE-2026-42448?
Upgrading to 0.24.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is magic-wormhole affected?
Yes, magic-wormhole is affected in releases prior to 0.24.0. Upgrade your dependency to 0.24.0 or later.
What is the CVSS score of CVE-2026-42448?
CVE-2026-42448 has a CVSS v3.1 base score of 3.5 (LOW) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N.
What CWE is associated with CVE-2026-42448?
CVE-2026-42448 is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.).
How can I check PyPI dependencies for CVE-2026-42448?
Run the dependency tree command: 'pip show magic-wormhole'. 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-cf92-gfcw-6v53",
  "modified" : "2026-06-08T23:28:03Z",
  "published" : "2026-05-06T20:40:17Z",
  "aliases" : [ "CVE-2026-42448" ],
  "summary" : "Magic Wormhole: receive, with --output pointing at an existing directory can be path-traversed",
  "details" : "### Impact\nA receiver who specifies \"--output <dir>\" where that output directory currently exists (as a directory).\n\n### Patches\n0.24.0 will contain the patch\n\n### Workarounds\nEnsure local target directories specified by \"--output\" do not already exist\n\n### Resources\nPrivate email and Signal communications from a user.\nMagic Wormhole thanks  @marduc812",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "magic-wormhole"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.23.0"
      }, {
        "fixed" : "0.24.0"
      } ]
    } ],
    "versions" : [ "0.23.0" ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/magic-wormhole/magic-wormhole/security/advisories/GHSA-cf92-gfcw-6v53"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-42448"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/magic-wormhole/magic-wormhole"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-06T20:40:17Z",
    "nvd_published_at" : "2026-05-26T18:16:48Z"
  }
}