Vulnerabilities in pkg:pypi/marshmallow

PACKAGE
Advisory Identifier: GHSA-428g-f7cq-pgp5
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Advisory Summary

CVE-2025-68480 is a MODERATE (CVSS 5.3) denial of service vulnerability (CWE-405: Asymmetric Resource Consumption (Amplification)) affecting Marshmallow libraries in the PyPI ecosystem. The issue involves marshmallow has dos in schema.load(many). Remediation is available by upgrading affected packages to version 3.26.2, 4.1.2.

2 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:pypi/marshmallow

2 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:pypi/marshmallow. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-428g-f7cq-pgp5 CVE-2025-68480 MODERATE Marshmallow has DoS in Schema.load(many)
GHSA-9q2p-fj49-vpxj CVE-2018-17175 MODERATE In marshmallow library the schema "only" option treats an empty list as implying no "only" option

CVE-2025-68480 at a Glance

CVE Identifier CVE-2025-68480
GHSA Identifier GHSA-428g-f7cq-pgp5
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-405: Asymmetric Resource Consumption (Amplification)
Affected Product Marshmallow
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 5.3

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:L).

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 Low (A:L)

How to Fix CVE-2025-68480

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

marshmallow fixed: 3.26.2 
pip install marshmallow>=3.26.2
marshmallow fixed: 4.1.2 
pip install marshmallow>=4.1.2
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 marshmallow

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2025-68480, inspect your installed packages using pip:

pip show marshmallow

Analyze the terminal output to locate any version of Marshmallow in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.26.2), your application is affected.

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

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-405: Asymmetric Resource Consumption (Amplification), where the product does not properly control situations in which an adversary can cause the product to consume or produce excessive resources without requiring the adversary to invest equivalent work or otherwise prove authorization, i.e., the adversary's influence is "asymmetric.". In Marshmallow, 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 `Schema.load(data, many=True)` is vulnerable to denial of service attacks. A moderately sized request can consume a disproportionate amount of CPU time. ### Patches 4.1.2, 3.26.2 ### Workarounds ```py # Fail fast def load_many(schema, data, **kwargs): if not isinstance(data, list): raise ValidationError(['Invalid input type.']) return [schema.load(item, **kwargs) for item in data] ```

CVE-2025-68480 Affected Marshmallow Versions

2 component(s)
Fixed Versions:
3.26.24.1.2
Product / Package Ecosystem Affected Versions Fixed Version
marshmallow
pypi/marshmallow
PyPI
≥ 3.0.0rc1
< 3.26.2
3.26.2
marshmallow
pypi/marshmallow
PyPI
≥ 4.0.0
< 4.1.2
4.1.2

References

GitHub Advisory / Wiki ADVISORY
https://github.com/marshmallow-code/marshmallow/security/advisories/GHSA-428g-f7cq-pgp5
NVD — CVE-2025-68480 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-68480
Security Fix Commit FIX COMMIT
https://github.com/marshmallow-code/marshmallow/commit/d24a0c9df061c4daa92f71cf85aca25b83eee508
Marshmallow Source Repository REPOSITORY
https://github.com/marshmallow-code/marshmallow

Frequently Asked Questions

What is CVE-2025-68480?
CVE-2025-68480 is a security vulnerability in Marshmallow involving Marshmallow has DoS in Schema.load(many) under CWE-405: Asymmetric Resource Consumption (Amplification).
Which Marshmallow versions are affected?
Affected versions include releases prior to 3.26.2, 4.1.2 across affected packages: marshmallow.
What version fixes CVE-2025-68480?
Upgrading to 3.26.2, 4.1.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is marshmallow affected?
Yes, marshmallow is affected in releases prior to 3.26.2, 4.1.2. Upgrade your dependency to 3.26.2, 4.1.2 or later.
What is the CVSS score of CVE-2025-68480?
CVE-2025-68480 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
What CWE is associated with CVE-2025-68480?
CVE-2025-68480 is classified under CWE-405: Asymmetric Resource Consumption (Amplification) (The product does not properly control situations in which an adversary can cause the product to consume or produce excessive resources without requiring the adversary to invest equivalent work or otherwise prove authorization, i.e., the adversary's influence is "asymmetric.").
How can I check PyPI dependencies for CVE-2025-68480?
Run the dependency tree command: 'pip show marshmallow'. 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-428g-f7cq-pgp5",
  "modified" : "2025-12-23T16:01:21Z",
  "published" : "2025-12-22T20:20:07Z",
  "aliases" : [ "CVE-2025-68480" ],
  "summary" : "Marshmallow has DoS in Schema.load(many)",
  "details" : "### Impact\n\n`Schema.load(data, many=True)` is vulnerable to denial of service attacks. A moderately sized request can consume a disproportionate amount of CPU time.\n\n### Patches\n\n4.1.2, 3.26.2\n\n### Workarounds\n\n```py\n# Fail fast\ndef load_many(schema, data, **kwargs):\n    if not isinstance(data, list):\n        raise ValidationError(['Invalid input type.'])\n    return [schema.load(item, **kwargs) for item in data]\n```",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "marshmallow"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.0.0rc1"
      }, {
        "fixed" : "3.26.2"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "marshmallow"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.0.0"
      }, {
        "fixed" : "4.1.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/marshmallow-code/marshmallow/security/advisories/GHSA-428g-f7cq-pgp5"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-68480"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/marshmallow-code/marshmallow/commit/d24a0c9df061c4daa92f71cf85aca25b83eee508"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/marshmallow-code/marshmallow"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-405" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-12-22T20:20:07Z",
    "nvd_published_at" : "2025-12-22T22:16:09Z"
  }
}