CVE-2021-214115.5MediumCWE-863

CVE-2021-21411: Incorrect authorization in OAuth2-Proxy

oauth2-proxy

Affected: oauth2-proxy · Exploitation: possible (1 to 10%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

1.1%probability of exploitation in the next 30 days

65th percentile

050100

Higher than 65% of scored CVEs

5.5MediumCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

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.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

oauth2-proxy · oauth2-proxy>= 7.0.0, < 7.1.0

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Possible (1 to 10%). EPSS between 1% and 10%.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Incorrect Authorization · Access Control
Vendor: oauth2-proxy
Published: March 2021
Band: Possible (1 to 10%), March 2021

CoverageNo articles yet

No CyberSIXT article names CVE-2021-21411 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.