User Authorization Flaw in Open WebUI AI Platform
CVE-2026-87994

4.3MEDIUM

Key Information:

Vendor

Open-webui

Status
Open-webui
Vendor
CVE Published:
9 September 2026

What is CVE-2026-87994?

Open WebUI versions 0.9.5 to 0.11.1 contain a vulnerability where the chat_completion endpoint fails to properly verify that a user is the author of a message before allowing modifications to it. This allows any channel member to replace messages authored by others while maintaining the original author's identity, posing a threat to the integrity of conversation records. The flaw has been rectified in version 0.11.1.

Affected Version(s)

open-webui >= 0.9.5, < 0.11.1

References

https://github.com/open-webui/open-webui/security/advisor...
x_refsource_CONFIRM
https://github.com/open-webui/open-webui/pull/28631
x_refsource_MISC
https://github.com/open-webui/open-webui/commit/7d392bedc...
x_refsource_MISC

CVSS V3.1

Score:
4.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.