Vulnerability in github.com/oauth2-proxy/oauth2-proxy/v7 (CVE-2021-21411)
Summary
Vulnerability in github.com/oauth2-proxy/oauth2-proxy/v7 (CVE-2021-21411). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 7.1.0 or later.
Original description
The description as published by the source.
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.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2021-21411 has been found in github.com/oauth2-proxy/oauth2-proxy/v7.
Risk of unauthorized operations or information disclosure.
What to do: upgrade github.com/oauth2-proxy/oauth2-proxy/v7 to 7.1.0 or later.
If unsure, ask your IT team or search "github.com/oauth2-proxy/oauth2-proxy/v7 CVE-2021-21411" on the vendor's site.
CVE-2021-21411 (github.com/oauth2-proxy/oauth2-proxy/v7) — CWE-285
Attack vector: remote (network-reachable) / no user interaction
Patched: 7.1.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-285) exists in github.com/oauth2-proxy/oauth2-proxy/v7.
Check the vendor advisory for the affected versions of github.com/oauth2-proxy/oauth2-proxy/v7.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 7.1.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'github.com/oauth2-proxy/oauth2-proxy/v7' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'github.com/oauth2-proxy/oauth2-proxy/v7' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
github.com/oauth2-proxy/oauth2-proxy/v7を grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade github.com/oauth2-proxy/oauth2-proxy/v7 to 7.1.0ステージング環境で 7.1.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory github.com
- advisory github.com
- advisory pkg.go.dev
- advisory docs.gitlab.com
- package github.com
- web nvd.nist.gov
- web docs.gitlab.com