CVE-2026-59221 open-webui terminal proxy path traversal guard bypass via 9x encoded traversal
Attackers can bypass path traversal protections in the terminal proxy via excessive encoding, potentially accessing unauthorized files or executing code.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-59221?
CVE-2026-59221 is a high-severity path traversal vulnerability in Openwebui Open Webui, published on 9 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.6 before 0.10.0, _sanitize_proxy_path in backend/open_webui/routers/terminals.py decoded proxy paths only eight times, allowing a nine-times percent-encoded ../ traversal value to pass normalization checks and be decoded by the upstream terminal server. This issue is fixed in version 0.10.0.
Which versions are affected by CVE-2026-59221?
3 open source packages ship an affected version, including open-webui. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
open-webui PyPI | From 0.9.6 | 0.10.0 |
open-webui PyPI | From 0.9.6 | 0.10.0 |
open-webui PyPI | From 0.9.6 | 0.10.0 |
Products include Openwebui Open Webui.
How do I fix CVE-2026-59221?
Upgrade open-webui to 0.10.0 or later.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-59221 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-59221 exists.
Other vulnerabilities in Openwebui Open Webui
- CVE-2026-44551 Open WebUI: LDAP Empty Password Authentication Bypass
- CVE-2026-56400 open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation
- CVE-2024-8017 Cross-site Scripting (XSS) in open-webui/open-webui
- CVE-2026-45672 Open WebUI: Jupyter code execution works despite `ENABLE_CODE_EXECUTION=false` — feature gate bypassed
- CVE-2026-87995 Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin
Sources
Also known as GHSA-frvj-c5qp-xj4w, PYSEC-2026-3597.