CVE-2026-48587

Potential exposure of private data via whitespace padding in Vary header

Published Jun 3, 2026 CVSS 4.0 · 2.3 Low EPSS < 1% KEV · Not listed
Description
An issue was discovered in Django 5.2 before 5.2.15 and 6.0 before 6.0.6.
`django.utils.cache.has_vary_header()` in Django does not strip leading or trailing whitespace from `Vary` response header values before comparison, which allows remote attackers to read cached responses via requests to URLs whose responses contain whitespace-padded Vary header values.
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 Navid Rezazadeh for reporting this issue.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Debian DLA Debian DLA DLA-4802-1 python-django security update
Github GHSA Github GHSA GHSA-923m-gv2p-w5qp Django: has_vary_header may expose cached responses when Vary values contain whitespace
History
Type Values Removed Values Added
CPEs cpe:2.3:a:djangoproject:django:*:*:*:*:*:*:*:*
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Djangoproject
Djangoproject django
Vendors & Products Djangoproject
Djangoproject django
Type Values Removed Values Added
Description An issue was discovered in Django 5.2 before 5.2.15 and 6.0 before 6.0.6. `django.utils.cache.has_vary_header()` in Django does not strip leading or trailing whitespace from `Vary` response header values before comparison, which allows remote attackers to read cached responses via requests to URLs whose responses contain whitespace-padded Vary header values. 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 Navid Rezazadeh for reporting this issue.
Title Potential exposure of private data via whitespace padding in Vary header
Weaknesses CWE-1023
References
Metrics cvssV3_1

{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N'}

cvssV4_0

{'score': 2.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
DSF
Published
Updated
Jun 3, 2026, 3:47 PM
Reserved
May 21, 2026, 8:50 PM
Status
Analyzed
Published
Jun 3, 2026, 2:16 PM
Modified
Jul 21, 2026, 7:10 PM
Severity
Low
Public date
Jun 3, 2026, 1:16 PM