CVE-2026-3902: ASGI header spoofing via underscore/hyphen conflation
Published Apr 7, 2026
·Updated
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.
Affected Software
6 affected componentsFixes available
pip/Django>=4.2<4.2.30
4.2.30
pip/Django>=5.2<5.2.13
5.2.13
pip/Django>=6.0<6.0.4
6.0.4
djangoproject Django>=4.2<4.2.30
djangoproject Django>=5.2<5.2.13
djangoproject Django>=6.0<6.0.4
Remediation
Patch Available
Event History
Apr 7, 2026
CVE Published
via MITRE·02:22 PM
Data Sourced
via MITRE·02:22 PM
DescriptionWeakness
Data Sourced
via NVD·03:17 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·03:17 PM
RemedyAffected Software
Advisory Published
via GitHub·03:30 PM
Data Sourced
via GitHub·03:30 PM
DescriptionSeverityWeaknessAffected Software