Authentication Bypass in open-webui (CVE-2026-70482)
Summary
Authentication bypass in open-webui (CVE-2026-70482). Confidential information can be exposed externally. Exploitable via POST /api/v1/auths/oauth/{provider}/token/exchange. Mitigation: upgrade to 0.11.0 or later.
Original description
The description as published by the source.
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.8.0 until 0.11.0, when ENABLE_OAUTH_TOKEN_EXCHANGE=True, /oauth/{provider}/token/exchange accepts a raw provider access token and validates it by calling the provider userinfo endpoint without confirming which OAuth client the token was issued to. Anyone holding an access token minted for any client registered with the same provider could exchange it for an Open WebUI session as that token user, including applications the operator does not control and has never authorized. This issue is fixed in 0.11.0.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
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-2026-70482 has been found in open-webui.
Attackers can target a specific entry point like POST /api/v1/auths/oauth/{provider}/token/exchange over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 8.1/10.
What to do: upgrade open-webui to 0.11.0 or later.
If unsure, ask your IT team or search "open-webui CVE-2026-70482" on the vendor's site.
CVE-2026-70482 (open-webui) — CWE-287 / CVSS v3 8.1
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: POST /api/v1/auths/oauth/{provider}/token/exchange / GET /api/v1/auths/ / OAUTH_MERGE_ACCOUNTS_BY_EMAIL / OAUTH_SUB_CLAIM
Patched: 0.11.0 — 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.
Authentication bypass (CWE-287) exists in open-webui. Attackers reach the vulnerable code path via POST /api/v1/auths/oauth/{provider}/token/exchange without authentication.
Check the vendor advisory for the affected versions of open-webui. Attack surface: POST /api/v1/auths/oauth/{provider}/token/exchange / GET /api/v1/auths/ / OAUTH_MERGE_ACCOUNTS_BY_EMAIL / OAUTH_SUB_CLAIM.
Severity: High (CVSS 8.1/10). Confidential information can be exposed externally.
Update to 0.11.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /api/v1/auths/oauth/{provider}/token/exchange requests with malformed payloads or SQL meta-characters. Run grep -r 'open-webui' . 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 'open-webui' . | 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
open-webuiを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /api/v1/auths/oauth/{provider}/token/exchange' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /api/v1/auths/oauth/{provider}/token/exchangeへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade open-webui to 0.11.0ステージング環境で 0.11.0 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と、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against POST /api/v1/auths/oauth/{provider}/token/exchange on staging to confirm patch closes the vector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 Step 2 と同じログクエリ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 nvd.nist.gov
- advisory github.com
- package github.com
- package pypi.org
- patch github.com
- patch github.com
- web github.com