Open WebUI: Any authenticated user can hang the server via a cyclic chat message history
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-835.
Summary
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.5.0 until 0.11.1, the message-chain reconstruction helper in backend/open_webui/utils/misc.py advanced through a chat history by map key but tracked visited entries using each message body's optional id field. An authenticated user could store id-less messages in a parent cycle and trigger a non-terminating walk that blocked the async event loop, grew memory until termination, and remained persistent across process restarts. This issue is fixed in version 0.11.1.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| open-webui | open-webui | 0.5.0 to before 0.11.1 | 0.11.1 | Patch available | CNA |
| — | open-webui (PyPI) | 0.5.0 to before 0.11.1 | 0.11.1 | Patch available | GHSA-jqhh-cjmq-vmv6 |
- open-webui Vendoropen-webui Affected 0.5.0 to before 0.11.1 Fixed in 0.11.1 Patch available CNA
- open-webui (PyPI) Vendor— Affected 0.5.0 to before 0.11.1 Fixed in 0.11.1 Patch available GHSA-jqhh-cjmq-vmv6
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:* | 0.5.0 to before 0.11.1 | Vulnerable | open-webui |
- cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:* Versions 0.5.0 to before 0.11.1 Vulnerable ·open-webui
Remediation
- Fix · CNA open-webui (open-webui) Fixed in 0.11.1
- Fix · GHSA-jqhh-cjmq-vmv6 open-webui (PyPI) Fixed in 0.11.1 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-88002
- 2026-10-03 Alias added: GHSA-jqhh-cjmq-vmv6
References
Patch 2
More open-webui Open Webui vulnerabilities
- TI-2024-06216 Open WebUI Arbitrary File Upload + Path Traversal CVSS 3.1HIGH 8.8
- TI-2024-07467 Improper Authentication in open-webui/open-webui CVSS 3.1HIGH 8.2
- TI-2026-42359 Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id CVSS 3.1CRITICAL 9.0
- TI-2026-40759 open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation CVSS 4.0CRITICAL 9.0
- TI-2024-07431 Cross-site Scripting (XSS) in open-webui/open-webui CVSS 3.0CRITICAL 9.0
- TI-2026-60021 Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin CVSS 3.1HIGH 8.7
Sources
- CVE-2026-88002 · CVE Program
- CVE-2026-88002 · NVD
- FIRST EPSS
- GHSA-jqhh-cjmq-vmv6 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences