CVE-2021-31542: Django Path Traversal Vulnerability

HIGH
Advisory Identifier: GHSA-rxjp-mfm9-w4wr
CVSS 7.5
CWE-434 CWE-22
Published
Advisory Summary

CVE-2021-31542 is a HIGH (CVSS 7.5) path traversal vulnerability (CWE-434: Unrestricted Upload of File with Dangerous Type) affecting Django libraries in the PyPI ecosystem. The issue involves path traversal in django. Remediation is available by upgrading affected packages to version 2.2.21, 3.1.9, 3.2.1.

CVE-2021-31542 at a Glance

CVE Identifier CVE-2021-31542
GHSA Identifier GHSA-rxjp-mfm9-w4wr
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-434: Unrestricted Upload of File with Dangerous Type
Affected Product Django
Package Ecosystem PyPI
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:H/I:N/A:N).

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 High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2021-31542

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

Django fixed: 2.2.21
pip install Django>=2.2.21
Django fixed: 3.1.9
pip install Django>=3.1.9
Django fixed: 3.2.1
pip install Django>=3.2.1
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 Django

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2021-31542, inspect your installed packages using pip:

pip show Django

Analyze the terminal output to locate any version of Django in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.2.21), your application is affected.

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

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-434: Unrestricted Upload of File with Dangerous Type, where the product allows the upload or transfer of dangerous file types that are automatically processed within its environment. In Django, 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

In Django 2.2 before 2.2.21, 3.1 before 3.1.9, and 3.2 before 3.2.1, MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.

CVE-2021-31542 Affected Django Versions

3 component(s)
Fixed Versions:
2.2.213.1.93.2.1
Product / Package Ecosystem Affected Versions Fixed Version
Django
PyPI
≥ 2.2
< 2.2.21
2.2.21
Django
PyPI
≥ 3.0
< 3.1.9
3.1.9
Django
PyPI
≥ 3.2
< 3.2.1
3.2.1

References

NVD — CVE-2021-31542 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-31542
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/04ac1624bdc2fa737188401757cf95ced122d26d
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/25d84d64122c15050a0ee739e859f22ddab5ac48
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/c98f446c188596d4ba6de71d1b77b4a6c5c2a007
Django Release RELEASE
https://www.djangoproject.com/weblog/2021/may/04/security-releases
Django Security Information SECURITY
https://security.netapp.com/advisory/ntap-20210618-0001
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZVKYPHR3TKR2ESWXBPOJEKRO2OSJRZUE
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/B4SQG2EAF4WCI2SLRL6XRDJ3RPK3ZRDV
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZVKYPHR3TKR2ESWXBPOJEKRO2OSJRZUE
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/B4SQG2EAF4WCI2SLRL6XRDJ3RPK3ZRDV
lists.debian.org/debian-lts-announce... WEB
https://lists.debian.org/debian-lts-announce/2021/05/msg00005.html
groups.google.com/forum/ WEB
https://groups.google.com/forum/#%21forum/django-announce
groups.google.com/forum/ WEB
https://groups.google.com/forum/#!forum/django-announce
Django Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2021-7.yaml
Django Source Repository REPOSITORY
https://github.com/django/django
GitHub Advisory / Wiki ADVISORY
https://github.com/advisories/GHSA-rxjp-mfm9-w4wr
Django Release RELEASE
https://docs.djangoproject.com/en/3.2/releases/security
Django Security Information SECURITY
http://www.openwall.com/lists/oss-security/2021/05/04/3

Frequently Asked Questions

What is CVE-2021-31542?
CVE-2021-31542 is a security vulnerability in Django involving Path Traversal in Django under CWE-434: Unrestricted Upload of File with Dangerous Type.
Which Django versions are affected?
Affected versions include releases prior to 2.2.21, 3.1.9, 3.2.1 across affected packages: Django.
What version fixes CVE-2021-31542?
Upgrading to 2.2.21, 3.1.9, 3.2.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is Django affected?
Yes, Django is affected in releases prior to 2.2.21, 3.1.9, 3.2.1. Upgrade your dependency to 2.2.21, 3.1.9, 3.2.1 or later.
What is the CVSS score of CVE-2021-31542?
CVE-2021-31542 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:H/I:N/A:N.
What CWE is associated with CVE-2021-31542?
CVE-2021-31542 is classified under CWE-434: Unrestricted Upload of File with Dangerous Type (The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.).
How can I check PyPI dependencies for CVE-2021-31542?
Run the dependency tree command: 'pip show Django'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-rxjp-mfm9-w4wr",
  "modified" : "2024-09-20T15:30:29Z",
  "published" : "2021-06-04T21:15:56Z",
  "aliases" : [ "CVE-2021-31542" ],
  "summary" : "Path Traversal in Django",
  "details" : "In Django 2.2 before 2.2.21, 3.1 before 3.1.9, and 3.2 before 3.2.1, MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "Django"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.2"
      }, {
        "fixed" : "2.2.21"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "Django"
    },
    "ranges" : [ {
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        "introduced" : "3.0"
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    } ]
  } ],
  "references" : [ {
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  }, {
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    "url" : "https://github.com/django/django/commit/04ac1624bdc2fa737188401757cf95ced122d26d"
  }, {
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    "url" : "https://github.com/django/django/commit/25d84d64122c15050a0ee739e859f22ddab5ac48"
  }, {
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    "url" : "https://github.com/django/django/commit/c98f446c188596d4ba6de71d1b77b4a6c5c2a007"
  }, {
    "type" : "WEB",
    "url" : "https://www.djangoproject.com/weblog/2021/may/04/security-releases"
  }, {
    "type" : "WEB",
    "url" : "https://security.netapp.com/advisory/ntap-20210618-0001"
  }, {
    "type" : "WEB",
    "url" : "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZVKYPHR3TKR2ESWXBPOJEKRO2OSJRZUE"
  }, {
    "type" : "WEB",
    "url" : "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/B4SQG2EAF4WCI2SLRL6XRDJ3RPK3ZRDV"
  }, {
    "type" : "WEB",
    "url" : "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZVKYPHR3TKR2ESWXBPOJEKRO2OSJRZUE"
  }, {
    "type" : "WEB",
    "url" : "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/B4SQG2EAF4WCI2SLRL6XRDJ3RPK3ZRDV"
  }, {
    "type" : "WEB",
    "url" : "https://lists.debian.org/debian-lts-announce/2021/05/msg00005.html"
  }, {
    "type" : "WEB",
    "url" : "https://groups.google.com/forum/#%21forum/django-announce"
  }, {
    "type" : "WEB",
    "url" : "https://groups.google.com/forum/#!forum/django-announce"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2021-7.yaml"
  }, {
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    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-rxjp-mfm9-w4wr"
  }, {
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    "url" : "https://docs.djangoproject.com/en/3.2/releases/security"
  }, {
    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2021/05/04/3"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22", "CWE-434" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-05-19T20:28:55Z",
    "nvd_published_at" : "2021-05-05T15:15:00Z"
  }
}