CVE-2026-59215 in Open WebUI
Summary
by MITRE • 07/09/2026
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, channel thread parent and reply handling did not bind parent_id to the channel in the URL, allowing an authenticated user to reference a message from another private or DM channel and disclose thread context across channels. This issue is fixed in version 0.10.0.
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Analysis
by VulDB Data Team • 07/10/2026
This vulnerability affects Open WebUI, a self-hosted AI platform that enables users to create and manage conversations within channels including private and direct message environments. The flaw existed in versions prior to 0.10.0 where the application failed to properly enforce channel boundaries when handling thread parent and reply operations. The technical implementation did not validate that referenced messages belonged to the currently accessed channel, creating a cross-channel information disclosure vulnerability.
The core issue stems from improper access control enforcement within the channel messaging system where parent_id references in URLs were not bound to channel context. When an authenticated user constructed a URL referencing a message thread from another private or DM channel, the application would display the referenced thread context without proper authorization checks. This represents a classic privilege escalation vulnerability where users could access data they should not be able to view based on their channel membership status.
From an operational perspective, this vulnerability allows authenticated attackers to potentially access sensitive information shared within private channels and direct messages by simply constructing appropriate URL parameters that reference messages from other channels. The impact extends beyond simple information disclosure as it undermines the fundamental security model of channel-based isolation that users expect in collaborative environments. This flaw could be exploited to gain unauthorized access to confidential conversations, user communications, and potentially sensitive data shared within private discussions.
The vulnerability aligns with CWE-284 (Improper Access Control) and represents a failure in implementing proper authorization checks at the application level. From an ATT&CK framework perspective, this maps to privilege escalation techniques where users can leverage application logic flaws to access resources beyond their intended scope. The fix implemented in version 0.10.0 addresses this by ensuring proper channel context binding during thread parent and reply handling operations, enforcing that all referenced message contexts must originate from the currently accessed channel.
Mitigation strategies should include immediate deployment of the patched version 0.10.0 or later, followed by comprehensive access control reviews of all channel-based messaging functionality. Organizations should implement additional monitoring for unusual URL parameter patterns that might indicate exploitation attempts. Security teams should also consider implementing automated scanning tools to detect similar cross-channel reference vulnerabilities in other applications within their environment. Regular security assessments focusing on access control mechanisms and proper authorization enforcement should be conducted to prevent similar issues from emerging in future releases.