CVE-2026-63439
CRITICAL
INFO
Priority: 0.04
BB Relevance:
80/100
Published: 2026-11-06
Modified: 2026-11-12
First seen: 2026-11-06
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
Conf. Impact
Integ. Impact
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
Unchanged
C:
High
I:
High
A:
High
Description
2FAuth is a web app to manage Two-Factor Authentication (2FA) accounts and generate their security codes. Prior to 8.0.0, when AUTHENTICATION_GUARD=reverse-proxy-guard is enabled, ReverseProxyGuard::user() reads the default REMOTE_USER identity header, or a custom identity header selected by the AUTH_PROXY_HEADER_FOR_USER configuration setting, without confirming that the request originated from a configured trusted proxy. A remote client that can reach the application directly can forge the selected identity header and authenticate as an existing user, including an administrator, gaining access to stored 2FA secrets and account or application management functions. This issue is fixed in version 8.0.0.
Weakness Classification (1)
References & Advisories (3)
x_refsource_MISC
x_refsource_MISC
x_refsource_CONFIRM