CVE-2026-87994

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.5 until 0.11.1, the channel branch of chat_completion in backend/open_webui/main.py checked channel write access and channel membership for a supplied message_id but did not verify that the calling user authored the targeted message. A channel member could use the chat completions endpoint to replace another member's message while preserving the victim as the stored author, altering the conversation record without gaining access to other channels. This issue is fixed in version 0.11.1.

• CWE-639
• CWE-862

• https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dc
• https://github.com/open-webui/open-webui/pull/28631
• https://github.com/open-webui/open-webui/releases/tag/v0.11.1
• https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8
• https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8

Published

Sep 9, 2026

Last Modified

Sep 10, 2026

Status

Undergoing Analysis

• Uncovering a hidden BOLA in Appsmith's snapshot logicStrix autonomously discovered a BOLA/IDOR vulnerability in Appsmith's snapshot deletion path.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2026-8795A YAML injection vulnerability exists in the Windows.Collect…7.8
• CVE-2026-8796Sereal::Decoder versions before 5.005 for Perl allow heap ou…8.1
• CVE-2026-87961ESP32-audioI2S versions 3.4.4 through 4.0.0 contain a heap-b…7.1
• CVE-2026-87962t-digest versions 3.1 through 3.3 contain a denial of servic…7.5
• CVE-2026-8797An access control deficiency vulnerability exists in Express…8.5
• CVE-2026-8798In Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 2.1.3…8.7
• CVE-2026-87995Open WebUI is an extensible, feature-rich, and user-friendly…8.7
• CVE-2026-87996Open WebUI is an extensible, feature-rich, and user-friendly…7.7
• CVE-2026-87997Open WebUI is an extensible, feature-rich, and user-friendly…4.3
• CVE-2026-87998Open WebUI is an extensible, feature-rich, and user-friendly…7.1
• CVE-2026-87999Open WebUI is an extensible, feature-rich, and user-friendly…7.1
• CVE-2026-8800Incorrect Authorization vulnerability in Progress MOVEit Tra…8.8