CVE-2026-87015 (GCVE-0-2026-87015)
Vulnerability from cvelistv5 – Published: 2026-09-09 21:03 – Updated: 2026-09-10 13:50
VLAI
EPSS
VEX
Title
Open WebUI: A user's session cookies are sent to tool servers configured for bearer authentication
Summary
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.6.27 until 0.11.1, backend/open_webui/utils/tools.py captured a cookie jar from the enclosing connection loop instead of binding it to each external tool callable. When multiple tool servers were attached and a session or system OAuth connection was processed last, a request to a different server configured for bearer authentication could include the calling user's Open WebUI session cookies, allowing that server's operator to reuse the session and take over the account. This issue is fixed in version 0.11.1.
Severity
6.8 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-10 13:50 UTC
CWE
- CWE-201 - Insertion of Sensitive Information Into Sent Data
Assigner
GitHub_M
CNA
References
4 references
| URL | Tags |
|---|---|
| https://github.com/open-webui/open-webui/security… | x_refsource_CONFIRM |
| https://github.com/open-webui/open-webui/pull/28630 | x_refsource_MISC |
| https://github.com/open-webui/open-webui/commit/c… | x_refsource_MISC |
| https://github.com/open-webui/open-webui/releases… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| open-webui | open-webui |
Affected:
>= 0.6.27, < 0.11.1
|
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