VU#754548: Cinnamon's Kotaemon contains improper authorization checks in Kotaemon multi‑user chat handlers

Date Sep 23, 2026
Type Coordinated disclosure
Signal Patch review
Vendor / Product Kotaemon · multi
Patch review

Summary

Overview Cinnamon's Kotaemon (all versions up to v0.12.0) multi‑user chat interface does not verify conversation ownership when loading a conversation. Any authenticated user can read, delete, rename, or overwrite another user’s conversation data by supplying the correct ID. This results in high‑impact confidentiality, integrity, and availability violations. Description Cinnamon's Kotaemon is an open‑source, retrieval‑augmented generation (RAG) based tool that lets you build a chatbot capable of "chatting with your documents". As discussed in CVE-2026-86867 , all versions up to v0.12.0 fail to verify conversation ownership when loading a conversation. In multi‑user mode, each conversation row includes a user field that identifies its owner. The four affected handlers, select_conv, delete_conv, rename_conv, and persist_chat_suggestions... Related CVEs: CVE-2026-86867.

Why it matters

CERT/CC notes often cover coordinated disclosures, multi-vendor exposure, infrastructure risk, or cases where remediation guidance is still developing.

Operator check

Review the CERT/CC Vulnerability Note and compare the affected vendor and product list against your inventory. Apply vendor fixes or compensating controls for multi where available.

Sources

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