CVE-2023-36053: Django Denial of Service Vulnerability

HIGH
Advisory Identifier: GHSA-jh3w-4vvf-mjgr
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CVSS 7.5
CWE-1333
Published
Advisory Summary

CVE-2023-36053 is a HIGH (CVSS 7.5) denial of service vulnerability (CWE-1333: Inefficient Regular Expression Complexity) affecting Django libraries in the PyPI ecosystem. The issue involves django has regular expression denial of service vulnerability in emailvalidator/urlvalidator. Remediation is available by upgrading affected packages to version 3.2.20, 4.1.10, 4.2.3.

CVE-2023-36053 at a Glance

CVE Identifier CVE-2023-36053
GHSA Identifier GHSA-jh3w-4vvf-mjgr
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-1333: Inefficient Regular Expression Complexity
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: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-2023-36053

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: 3.2.20 
pip install Django>=3.2.20
Django fixed: 4.1.10 
pip install Django>=4.1.10
Django fixed: 4.2.3 
pip install Django>=4.2.3
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-2023-36053, 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 3.2.20), 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-1333: Inefficient Regular Expression Complexity, where the product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential. 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 3.2 before 3.2.20, 4 before 4.1.10, and 4.2 before 4.2.3, `EmailValidator` and `URLValidator` are subject to a potential ReDoS (regular expression denial of service) attack via a very large number of domain name labels of emails and URLs.

CVE-2023-36053 Affected Django Versions

3 component(s)
Fixed Versions:
3.2.204.1.104.2.3
Product / Package Ecosystem Affected Versions Fixed Version
Django
pypi/Django
PyPI
≥ 3.2a1
< 3.2.20
3.2.20
Django
pypi/Django
PyPI
≥ 4.0a1
< 4.1.10
4.1.10
Django
pypi/Django
PyPI
≥ 4.2a1
< 4.2.3
4.2.3

References

NVD — CVE-2023-36053 NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-36053
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/454f2fb93437f98917283336201b4048293f7582
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/ad0410ec4f458aa39803e5f6b9a3736527062dcd
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/b7c5feb35a31799de6e582ad6a5a91a9de74e0f9
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/beb3f3d55940d9aa7198bf9d424ab74e873aec3d
Django Release RELEASE
https://www.djangoproject.com/weblog/2023/jul/03/security-releases
Django Security Information SECURITY
https://www.debian.org/security/2023/dsa-5465
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZQJOMNRMVPCN5WMIZ7YSX5LQ7IR2NY4D
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XG5DYKPNDCEHJQ3TKPJQO7QGSR4FAYMS
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NRDGTUN4LTI6HG4TWR3JYLSFVXPZT42A
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZQJOMNRMVPCN5WMIZ7YSX5LQ7IR2NY4D
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XG5DYKPNDCEHJQ3TKPJQO7QGSR4FAYMS
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NRDGTUN4LTI6HG4TWR3JYLSFVXPZT42A
lists.debian.org/debian-lts-announce... WEB
https://lists.debian.org/debian-lts-announce/2023/07/msg00022.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-2023-100.yaml
Django Source Repository REPOSITORY
https://github.com/django/django
Django Release RELEASE
https://docs.djangoproject.com/en/4.2/releases/security

Frequently Asked Questions

What is CVE-2023-36053?
CVE-2023-36053 is a security vulnerability in Django involving Django has regular expression denial of service vulnerability in EmailValidator/URLValidator under CWE-1333: Inefficient Regular Expression Complexity.
Which Django versions are affected?
Affected versions include releases prior to 3.2.20, 4.1.10, 4.2.3 across affected packages: Django.
What version fixes CVE-2023-36053?
Upgrading to 3.2.20, 4.1.10, 4.2.3 (or the latest patched release for your respective branch) resolves the vulnerability.
Is Django affected?
Yes, Django is affected in releases prior to 3.2.20, 4.1.10, 4.2.3. Upgrade your dependency to 3.2.20, 4.1.10, 4.2.3 or later.
What is the CVSS score of CVE-2023-36053?
CVE-2023-36053 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-2023-36053?
CVE-2023-36053 is classified under CWE-1333: Inefficient Regular Expression Complexity (The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.).
How can I check PyPI dependencies for CVE-2023-36053?
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
View Raw JSON 
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  "id" : "GHSA-jh3w-4vvf-mjgr",
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