CVE-2026-33433

high Red Hat
CVSS v3 Base Score
7.7
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:N
EPSS Score
0.0%
Exploitation probability in 30 days
Top 99% most likely to be exploited
Attack Characteristics
Attack Vector
Network
Attack Complexity
High
Privileges Required
High
User Interaction
None
Confidentiality
High
Integrity
High
Availability
None
Published: March 27, 2026 (48 days ago)
Last Modified: March 27, 2026
Vendor: Red Hat
Source: REDHAT

Description

Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.42, 3.6.11, and 3.7.0-ea.3, when `headerField` is configured with a non-canonical HTTP header name (e.g., `x-auth-user` instead of `X-Auth-User`), an authenticated attacker can inject their own canonical version of that header to impersonate any identity to the backend. The backend receives two header entries — the attacker-injected canonical one is read first, overriding Traefik's non-canonical write. Versions 2.11.42, 3.6.11, and 3.7.0-ea.3 patch the issue.

CWE

CWE-290

Affected Products

Red Hat OpenShift Dev Spaces

References

🔗 bugzilla.redhat.com 🔗 www.cve.org 🔗 nvd.nist.gov 🔗 github.com 🔗 github.com