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CVE-2026-3902

ASGI header spoofing via underscore/hyphen conflation

Published: Apr 7, 2026Updated: Apr 13, 2026 Sources: CVE List NVD BDUCWE-290
7.5HIGH
NVD MITRE
EPSS Score
0.4%
Top 64.1%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

An issue was discovered in 6.0 before 6.0.4, 5.2 before 5.2.13, and 4.2 before 4.2.30. `ASGIRequest` allows a remote attacker to spoof headers by exploiting an ambiguous mapping of two header variants (with hyphens or with underscores) to a single version with underscores. 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 Tarek Nakkouch for reporting this issue.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-290

Affected Products

Red Hat Inc.
commercial·USaka red hat
Red Hat SatelliteOn-prem
Operating Systems / linux-distro
DiscoveryOn-prem
Operating Systems / linux-distro
Ansible Automation PlatformOn-prem
Operating Systems / linux-distro
djangoproject
oss-projectaka django
Django
OSS Libraries
Canonical Ltd.
commercial·GBaka canonical
UbuntuOn-premOS
Operating Systems / linux-distro
ООО «Ред Софт»
commercial·RUaka red soft
РЕД ОСOn-premOS
Operating Systems / linux-distro
Django Software Foundation
oss-project·USaka django
DjangoLibraryLibrary
OSS Libraries / web-framework
and 1 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Initial Access
View detailed technique mapping

References

https://docs.djangoproject.com/en/dev/releases/security/
docs.djangoproject.com
https://groups.google.com/g/django-announce
groups.google.com
https://www.djangoproject.com/weblog/2026/apr/07/security-releases/
djangoproject.com
and 6 more references View all →

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