Path Traversal in open-webui (CVE-2026-59221)
Summary
Path traversal in open-webui (CVE-2026-59221). Confidential information can be exposed externally. Mitigation: upgrade to 0.10.0 or later.
Original description
The description as published by the source.
AI assistance was used to help inspect the code and prepare this report.
Summary
The fix for GHSA-r2wg-2mcr-66rv is incomplete in v0.9.6 and current main. backend/open_webui/routers/terminals.py documents _sanitize_proxy_path() as decoding until stable, but the implementation stops after 8 unquote() passes. A 9x percent-encoded ../... path parameter remains once-encoded after the loop, passes the posixpath.normpath() and cleaned.startswith('..') checks, and is forwarded to the configured terminal server. The upstream server then receives a decoded traversal path such as /base/../admin/system.
Impact
A user who has access to an admin-configured terminal connection can bypass the terminal proxy path traversal guard and cause Open WebUI to forward requests with the configured terminal credentials and X-User-Id header to paths outside the intended normalized proxy path. For orchestrator-backed terminal connections the same sanitized path is placed under /p/{policy_id}/{safe_path}, so the bypass can also target sibling or parent routes after upstream decoding. This is a bypass of the same terminal proxy boundary covered by GHSA-r2wg-2mcr-66rv.
This does not require adding a malicious terminal server or convincing an administrator to weaken settings. The attacker only needs normal access to an existing configured terminal connection.
Reproduction
The following standalone Python script mirrors the current sanitizer and uses a local aiohttp server as…
Source: NIST National Vulnerability Database 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-2026-59221 has been found in open-webui.
Confidential information can be exposed externally. CVSS score: 7.7/10.
What to do: upgrade open-webui to 0.10.0 or later.
If unsure, ask your IT team or search "open-webui CVE-2026-59221" on the vendor's site.
CVE-2026-59221 (open-webui) — CWE-22 / CVSS v3 7.7
Attack vector: remote (network-reachable) / no user interaction
Patched: 0.10.0 — 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.
Path traversal (CWE-22) exists in open-webui.
Check the vendor advisory for the affected versions of open-webui.
Severity: High (CVSS 7.7/10). Confidential information can be exposed externally.
Update to 0.10.0.
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 '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
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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。 -
2Apply patch patch
Upgrade open-webui to 0.10.0ステージング環境で 0.10.0 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。
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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 nvd.nist.gov
- advisory github.com
- package github.com
- package pypi.org
- web github.com
- web github.com
- web github.com
- web github.com