Information Disclosure in open-webui (CVE-2026-70491)
Summary
Vulnerability in open-webui (CVE-2026-70491). Confidential information can be exposed externally. Exploitable via GET /api/v1/tools/. Mitigation: upgrade to 0.11.0 or later.
Original description
The description as published by the source.
Summary
A workspace tool shared with a read grant returned its full Python source to the recipient. Any authenticated non-admin who could use a shared tool could also read its source, including any user on the instance when a tool was shared publicly. Source is meant to be a writer-only tier: the list response schema deliberately omits it and source export sits behind its own permission. The read endpoints delivered it anyway.
Preconditions
- Authentication enabled (
WEBUI_AUTH=true, default) and plugins enabled (ENABLE_PLUGINS=true, default). - The attacker is an authenticated non-admin without the
workspace.toolspermission and without a write grant on the tool. - A tool is shared with a read grant to the attacker, to one of their groups, or to all users (
user:*).
Deployments that share no tools, or share them only with users who already hold write access, are not affected.
Impact
A non-admin obtains another user's server-side tool source. Tool source commonly embeds hard-coded API keys, credentials and internal service URLs, so the practical loss frequently extends past the code itself. The attack needs no special permission beyond an ordinary account that a tool was shared with, and no user interaction. Confidentiality only: it grants no ability to create, modify or execute tools, and no integrity or availability impact.
Fix
Fixed in 0.11.0 by commit c05de13b4 (#27005) together with 310ae9130. The per-id endpoint now drops the source for cal…
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-2026-70491 has been found in open-webui.
Attackers can target a specific entry point like GET /api/v1/tools/ over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 6.5/10.
What to do: upgrade open-webui to 0.11.0 or later.
If unsure, ask your IT team or search "open-webui CVE-2026-70491" on the vendor's site.
CVE-2026-70491 (open-webui) — CWE-200 / CVSS v3 6.5
Attack vector: remote (network-reachable) / no user interaction
Attack surface: GET /api/v1/tools/ / GET /api/v1/tools/list / GET /api/v1/tools/id/{id} / POST /api/v1/tools/create
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.
Information disclosure (CWE-200) exists in open-webui. Attackers reach the vulnerable code path via GET /api/v1/tools/.
Check the vendor advisory for the affected versions of open-webui. Attack surface: GET /api/v1/tools/ / GET /api/v1/tools/list / GET /api/v1/tools/id/{id} / POST /api/v1/tools/create.
Severity: Medium (CVSS 6.5/10). 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 GET /api/v1/tools/ 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 'GET /api/v1/tools/' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /api/v1/tools/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 GET /api/v1/tools/ 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 nvd.nist.gov
- package github.com
- package pypi.org
- web github.com
- web github.com
- web github.com
- web github.com