CVE-2026-53878: Django DomainNameValidator Permits Newline Characters That Vulnerability

MODERATE
Advisory Identifier: GHSA-8qcx-xf44-272x
Share
CVSS 6.1
CWE-144
Published
Advisory Summary

CVE-2026-53878 is a MODERATE (CVSS 6.1) domainnamevalidator permits newline characters that vulnerability (CWE-144: Improper Neutralization of Line Delimiters) affecting Django libraries in the PyPI ecosystem. The issue involves domainnamevalidator permits newline characters that may enable http header injection. Remediation is available by upgrading affected packages to version 5.2.16, 6.0.7.

CVE-2026-53878 at a Glance

CVE Identifier CVE-2026-53878
GHSA Identifier GHSA-8qcx-xf44-272x
Severity MODERATE
CVSS v3.1 Base Score 6.1
CWE Classification CWE-144: Improper Neutralization of Line Delimiters
Affected Product Django
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 6.1

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:R/S:C/C:L/I:L/A:N).

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

How to Fix CVE-2026-53878

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: 5.2.16 
pip install django>=5.2.16
django fixed: 6.0.7 
pip install django>=6.0.7
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-2026-53878, 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 5.2.16), 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-144: Improper Neutralization of Line Delimiters, where the product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as line delimiters when they are sent to a downstream component. 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

An issue was discovered in Django 6.0 before 6.0.7 and 5.2 before 5.2.16. `DomainNameValidator` does not prohibit newlines in domain names (unless used via a form field, since `CharField` strips newlines). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because `HttpResponse` prohibits newlines in HTTP headers. Earlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected. Django would like to thank Bence Nagy for reporting this issue.

CVE-2026-53878 Affected Django Versions

2 component(s)
Fixed Versions:
5.2.166.0.7
Product / Package Ecosystem Affected Versions Fixed Version
django
pypi/django
PyPI
< 5.2.16
5.2.16
django
pypi/django
PyPI
≥ 6.0.0
< 6.0.7
6.0.7

References

NVD — CVE-2026-53878 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-53878
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/3a720d0d8bf2529253b98968f10ca73daf6d693c
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/a5de13f1491f1dbf2bb0ad9b91570524ebbc8acd
Security Fix Commit FIX COMMIT
https://github.com/django/django/commit/d5d60ed0323cddaa0ce0237a26a3d49ac21ee05e
Django Release RELEASE
https://docs.djangoproject.com/en/dev/releases/security
Django Source Repository REPOSITORY
https://github.com/django/django
Django Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2026-2092.yaml
groups.google.com/g/django-announce WEB
https://groups.google.com/g/django-announce
Django Release RELEASE
https://www.djangoproject.com/weblog/2026/jul/07/security-releases

Frequently Asked Questions

What is CVE-2026-53878?
CVE-2026-53878 is a security vulnerability in Django involving DomainNameValidator permits newline characters that may enable HTTP header injection under CWE-144: Improper Neutralization of Line Delimiters.
Which Django versions are affected?
Affected versions include releases prior to 5.2.16, 6.0.7 across affected packages: django.
What version fixes CVE-2026-53878?
Upgrading to 5.2.16, 6.0.7 (or the latest patched release for your respective branch) resolves the vulnerability.
Is django affected?
Yes, django is affected in releases prior to 5.2.16, 6.0.7. Upgrade your dependency to 5.2.16, 6.0.7 or later.
What is the CVSS score of CVE-2026-53878?
CVE-2026-53878 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2026-53878?
CVE-2026-53878 is classified under CWE-144: Improper Neutralization of Line Delimiters (The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as line delimiters when they are sent to a downstream component.).
How can I check PyPI dependencies for CVE-2026-53878?
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 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-8qcx-xf44-272x",
  "modified" : "2026-08-07T20:00:49Z",
  "published" : "2026-07-07T15:32:57Z",
  "aliases" : [ "CVE-2026-53878" ],
  "summary" : "Django: DomainNameValidator permits newline characters that may enable HTTP header injection",
  "details" : "An issue was discovered in Django 6.0 before 6.0.7 and 5.2 before 5.2.16.\n`DomainNameValidator` does not prohibit newlines in domain names (unless used via a form field, since `CharField` strips newlines). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because `HttpResponse` prohibits newlines in HTTP headers.\nEarlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected.\nDjango would like to thank Bence Nagy for reporting this issue.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "django"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "5.2.16"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "django"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "6.0.0"
      }, {
        "fixed" : "6.0.7"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-53878"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/django/django/commit/3a720d0d8bf2529253b98968f10ca73daf6d693c"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/django/django/commit/a5de13f1491f1dbf2bb0ad9b91570524ebbc8acd"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/django/django/commit/d5d60ed0323cddaa0ce0237a26a3d49ac21ee05e"
  }, {
    "type" : "WEB",
    "url" : "https://docs.djangoproject.com/en/dev/releases/security"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/django/django"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2026-2092.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://groups.google.com/g/django-announce"
  }, {
    "type" : "WEB",
    "url" : "https://www.djangoproject.com/weblog/2026/jul/07/security-releases"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-144" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-08-07T20:00:49Z",
    "nvd_published_at" : "2026-07-07T15:16:48Z"
  }
}