CVE-2026-87994

    Dashboard / Vulnerabilities / CVE-2026-87994

    CVE-2026-87994

    Published: 9 Sept 2026Last Modified: 12 Sept 2026

    Summary: Open WebUI: Channel members can overwrite another member's message via the chat completions endpoint

    Details: 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.

    References: https://github.com/open-webui/open-webui/releases/tag/v0.11.1, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/87xxx/CVE-2026-87994.json, https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8, https://nvd.nist.gov/vuln/detail/CVE-2026-87994, https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dc, https://github.com/open-webui/open-webui/pull/28631

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: GIT

    Events:

    Introduced- 3660bc00fd807deced3400a63bfa6db47811a3bb
    Fixed -7d392bedc9c1aaecc94509a58e59186b614433dc

    Affected versions

    v0.11.0

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    CVE-2026-87994 | CVE-DB