CVE-2026-87015CWE-201

CVE-2026-87015

Medium · published September 10, 2026

CVSS v3.1
6.8
EPSS
0%
Percentile
40.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.8 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00478 · 40.3th percentile
Weakness
CWE-201 · Insertion of Sensitive Information Into Sent Data
Published
2026-09-10T01:17Z
Affected products (1)
ProductVersionsFixed in
openwebui/open_webui≥ 0.6.27, < 0.11.10.11.1
References (5)
EPSS history
Timeline
  • 11 SEP 03:19Z
    EPSS moved — → 0%
    epss
  • 09 SEP 21:03Z
    Open WebUI: A user's session cookies are sent to tool servers configured for bearer authentication
    cvelistv5