CVE-2021-21411

OAuth2-Proxy is an open source reverse proxy that provides authentication with Google, Github or other providers. The `--gitlab-group` flag for group-based authorization in the GitLab provider stopped working in the v7.0.0 release. Regardless of the flag settings, authorization wasn't restricted. Additionally, any authenticated users had whichever groups were set in `--gitlab-group` added to the new `X-Forwarded-Groups` header to the upstream application. While adding GitLab project based authorization support in #630, a bug was introduced where the user session's groups field was populated with the `--gitlab-group` config entries instead of pulling the individual user's group membership from the GitLab Userinfo endpoint. When the session groups where compared against the allowed groups for authorization, they matched improperly (since both lists were populated with the same data) so authorization was allowed. This impacts GitLab Provider users who relies on group membership for authorization restrictions. Any authenticated users in your GitLab environment can access your applications regardless of `--gitlab-group` membership restrictions. This is patched in v7.1.0. There is no workaround for the Group membership bug. But `--gitlab-project` can be set to use Project membership as the authorization checks instead of groups; it is not broken.
Configurations

Configuration 1 (hide)

cpe:2.3:a:oauth2_proxy_project:oauth2_proxy:*:*:*:*:*:*:*:*

History

06 Apr 2021, 12:42

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown
v2 : 5.5
v3 : 5.5
References (MISC) https://docs.gitlab.com/ee/user/group/ - (MISC) https://docs.gitlab.com/ee/user/group/ - Third Party Advisory
References (MISC) https://pkg.go.dev/github.com/oauth2-proxy/oauth2-proxy/v7 - (MISC) https://pkg.go.dev/github.com/oauth2-proxy/oauth2-proxy/v7 - Product, Third Party Advisory
References (MISC) https://github.com/oauth2-proxy/oauth2-proxy/commit/0279fa7dff1752f1710707dbd1ffac839de8bbfc - (MISC) https://github.com/oauth2-proxy/oauth2-proxy/commit/0279fa7dff1752f1710707dbd1ffac839de8bbfc - Patch, Third Party Advisory
References (CONFIRM) https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-652x-m2gr-hppm - (CONFIRM) https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-652x-m2gr-hppm - Third Party Advisory
References (MISC) https://github.com/oauth2-proxy/oauth2-proxy/releases/tag/v7.1.0 - (MISC) https://github.com/oauth2-proxy/oauth2-proxy/releases/tag/v7.1.0 - Release Notes, Third Party Advisory
CPE cpe:2.3:a:oauth2_proxy_project:oauth2_proxy:*:*:*:*:*:*:*:*

26 Mar 2021, 21:27

Type Values Removed Values Added
New CVE

Information

Published : 2021-03-26 21:15

Updated : 2023-12-10 13:55


NVD link : CVE-2021-21411

Mitre link : CVE-2021-21411

CVE.ORG link : CVE-2021-21411


JSON object : View

Products Affected

oauth2_proxy_project

  • oauth2_proxy
CWE
CWE-863

Incorrect Authorization