CVE-2026-82281 in Kotaemon
Summary
by MITRE • 08/28/2026
Kotaemon through 0.12.0 fails to properly validate conversation ownership in select_conv, delete_conv, rename_conv, and on_set_public_conversation functions in control.py. Attackers can read other users' chat histories, delete conversations, or rename conversations by supplying arbitrary conversation identifiers without proper authorization checks.
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Analysis
by VulDB Data Team • 08/28/2026
The vulnerability identified in Kotaemon versions through 0.12.0 represents a critical failure in access control mechanisms within the application's core conversational management logic. Specifically, the flaw resides in four distinct functions located in the control.py module: select_conv, delete_conv, rename_conv, and on_set_public_conversation. These functions are responsible for managing user interactions with chat sessions, including switching between conversations, removing them entirely, modifying their metadata such as titles, and adjusting visibility settings. The root cause of this insecurity is a complete absence or insufficient implementation of authorization checks regarding conversation ownership. When these endpoints are invoked by an authenticated user, the application fails to verify that the requesting user is the legitimate owner of the specified conversation identifier before executing the requested action. This design oversight allows any authenticated attacker who can guess or obtain valid conversation identifiers to interact with conversations belonging to other users on the same instance.
From a technical perspective, this vulnerability constitutes an Insecure Direct Object Reference (IDOR), which corresponds to CWE-639 in the Common Weakness Enumeration standard. The application relies on client-supplied or easily predictable conversation IDs without binding these resources to the session context of the authenticated user. By manipulating the input parameters passed to select_conv, delete_conv, rename_conv, and on_set_public_conversation, an attacker can bypass intended security boundaries. For instance, supplying a different user's conversation ID in the delete_conv function results in the permanent removal of that other user's chat history without any permission verification. Similarly, using arbitrary identifiers in select_conv or rename_conv allows the attacker to view private messages and alter the metadata associated with conversations they do not own. This behavior violates the principle of least privilege and fails to enforce proper object-level access controls, which are fundamental requirements for secure web application development as outlined in OWASP guidelines regarding broken access control vulnerabilities.
The operational impact of this vulnerability is severe, affecting both confidentiality and integrity within the multi-user environment provided by Kotaemon. The ability to read other users' chat histories exposes sensitive information that may include personal data, proprietary business discussions, or private communications, leading to significant privacy breaches. Furthermore, the capability to delete conversations results in a denial of service for the affected victims, as their historical context and records are irretrievably lost unless backups exist. The ability to rename conversations introduces integrity issues, potentially causing confusion among users who rely on accurate conversation titles for organization and retrieval. In environments where Kotaemon is used for customer support or internal team collaboration, these actions can disrupt workflows, damage trust in the platform's reliability, and expose organizations to compliance risks related to data protection regulations such as GDPR or HIPAA if sensitive information is involved.
This vulnerability aligns with several tactics within the MITRE ATT&CK framework, particularly those related to Collection and Impact. The unauthorized reading of chat histories falls under Data from Information Repositories (T1213), where an adversary accesses stored data without proper authorization. The deletion of conversations corresponds to Destruction (TA0040) or specifically Impair Defenses by deleting logs or records if the system is used for audit purposes, though more directly it impacts Availability and Integrity. To mitigate this issue, developers must implement strict server-side validation that ensures every request to modify or access a conversation includes an explicit check verifying that the authenticated user's identity matches the owner of the target resource. This involves querying the database with both the conversation ID and the current user's session token or user ID to confirm ownership before proceeding with any operation. Additionally, implementing rate limiting and logging for these endpoints can help detect anomalous behavior indicative of enumeration attacks where attackers attempt to guess valid conversation IDs. Upgrading to a patched version that resolves this access control flaw is essential for maintaining the security posture of deployed Kotaemon instances.