CVE-2026-86867

Description

Cinnamon's Kotaemon (all versions up to and including v0.12.0) multi-user chat interface contains multiple vulnerabilities due to incorrect authorization and improper access controls. There are four handler methods in `libs/ktem/ktem/pages/chat/control.py` that load a Conversation record by its ID without comparing the requester's `user_id` to the conversation's owner `Conversation.user`. This allows any authenticated user to perform the following actions: 1. Read other user's chat transcripts, RAG retrieval history, AI-generated plots, and chat suggestions. 2. Permanently delete another user's conversation. 3. Rename another user's conversation. 4. Overwrite another user's conversation's chat suggestion list.

Overview

State: PUBLISHED
Assigner (CNA): certcc
CVSS severity: —
CVSS score: —
CVSS vector: —
Effective score: no score available from CNA, NVD, or AI yet
CWE(s): CWE-862 Missing Authorization, CWE-639 Authorization Bypass Through User-Controlled Key, CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
Reserved: 2026-09-08
Published: 2026-09-23 17:44 UTC
Last updated: 2026-09-23 18:10 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/86xxx/CVE-2026-86867.json

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NVD published: 2026-09-23 18:17:09 UTC
NVD last modified: 2026-09-23 19:19:42 UTC

AI-forensic CVSS estimate

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European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-85508
Assigner: certcc
Published: Sep 23, 2026, 5:44:52 PM
Updated: Sep 23, 2026, 6:10:51 PM
EUVD base score: 0.0 / 10
EUVD-reported EPSS: 0.0000
Vendors: Cinnamon AI
Products: kotaemon (0.12.0)
Aliases: GHSA-xj3r-7j9q-cqf2

ENISA description: Cinnamon's Kotaemon (all versions up to and including v0.12.0) multi-user chat interface contains multiple vulnerabilities due to incorrect authorization and improper access controls. There are four handler methods in `libs/ktem/ktem/pages/chat/control.py` that load a Conversation record by its ID without comparing the requester's `user_id` to the conversation's owner `Conversation.user`. This allows any authenticated user to perform the following actions: 1. Read other user's chat transcripts, RAG retrieval history, AI-generated plots, and chat suggestions. 2. Permanently delete another user's conversation. 3. Rename another user's conversation. 4. Overwrite another user's conversation's chat suggestion list.

EUVD references (1)

https://kb.cert.org/vuls/id/754548

Affected products (1)

Vendor	Product	Versions	Platforms
Cinnamon AI	Kotaemon	`0.12.0` (affected)	—

Vendor references (1)

References embedded in the original CVE record by the assigning CNA.

https://kb.cert.org/vuls/id/754548

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (2)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://kb.cert.org/vuls/id/754548 cret@cert.org
https://www.kb.cert.org/vuls/id/754548 af854a3a-2127-422b-91ae-364da2661108

Remediations (10)

July 2026 Critical Patch Update Released | security - Oracle Blogs

web:blogs.oracle.com

For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.

2026-09-24 11:48 UTC
Cisco Advance Notification for Publication of September 16, 2026 ...

web:sec.cloudapps.cisco.com

On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...

2026-09-24 11:48 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-24 11:48 UTC
About the security content of iOS 26.7 and iPadOS 26.7

web:support.apple.com

This document describes the security content of iOS 26.7 and iPadOS 26.7.

2026-09-24 11:48 UTC
Description of the security update for Office 2016: August 11, 2026 ...

web:support.microsoft.com

Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...

2026-09-24 11:48 UTC
SAP Security Patch Day - June 2026

web:support.sap.com

SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.

2026-09-24 11:48 UTC
Oracle Critical Patch Update Advisory - July 2026

web:www.oracle.com

This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-24 11:48 UTC
Oracle Critical Security Patch Update Advisory - June 2026

web:www.oracle.com

Additional CVEs addressed are: The patch for CVE - 2026 -34481 also addresses CVE - 2026 -34477, CVE - 2026 -34478, CVE - 2026 -34479, and CVE - 2026 -34480. Oracle Fusion Middleware Risk Matrix This Critical Security Patch Update contains 106 new security patches for Oracle Fusion Middleware. 53 of these vulnerabilities may be remotely exploitable without authentication, i.e., may be exploited over a ...

2026-09-24 11:48 UTC
Vulnerabilities Resolved in Veeam Backup & Replication 13.0.1.2067

web:www.veeam.com

When a vulnerability is identified, our team promptly develops a patch to address and mitigate the risk. In line with our dedication to transparency, we publicly disclose the vulnerability and provide detailed mitigation information.

2026-09-24 11:48 UTC
WhatsApp Security Advisories 2026

web:www.whatsapp.com

CVE - 2026 -23863 An attachment spoofing issue in WhatsApp for Windows prior to v2.3000.1032164386.258709 could have allowed maliciously formatted documents with embedded NUL bytes in the filename to be shown in the application as one type of file but run as an executable when opened. We have not seen evidence of exploitation in the wild. Acknowledgements: External Researcher via Meta Bug Bounty ...

2026-09-24 11:48 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-86867.json.

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2026-09-23T18:10:51.647Z",
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          "shortName": "CVE"
        },
        "references": [
          {
            "url": "https://www.kb.cert.org/vuls/id/754548"
          }
        ],
        "title": "CVE Program Container"
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    ],
    "cna": {
      "affected": [
        {
          "product": "Kotaemon",
          "vendor": "Cinnamon AI",
          "versions": [
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            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Cinnamon's Kotaemon (all versions up to and including v0.12.0) multi-user chat interface contains multiple vulnerabilities due to incorrect authorization and improper access controls. There are four handler methods in `libs/ktem/ktem/pages/chat/control.py` that load a Conversation record by its ID without comparing the requester's `user_id` to the conversation's owner `Conversation.user`. This allows any authenticated user to perform the following actions:\r\n1. Read other user's chat transcripts, RAG retrieval history, AI-generated plots, and chat suggestions.\r\n2. Permanently delete another user's conversation.\r\n3. Rename another user's conversation.\r\n4. Overwrite another user's conversation's chat suggestion list."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-862 Missing Authorization",
              "lang": "en"
            }
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        },
        {
          "descriptions": [
            {
              "description": "CWE-639 Authorization Bypass Through User-Controlled Key",
              "lang": "en"
            }
          ]
        },
        {
          "descriptions": [
            {
              "description": "CWE-200 Exposure of Sensitive Information to an Unauthorized Actor",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
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      },
      "references": [
        {
          "url": "https://kb.cert.org/vuls/id/754548"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Cinnamon's kotaemon contains improper authorization checks in multi\u2011user chat handlers",
      "x_generator": {
        "engine": "VINCE 3.0.49",
        "env": "prod",
        "origin": "https://cveawg.mitre.org/api/cve/CVE-2026-86867"
      }
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  },
  "cveMetadata": {
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    "dateReserved": "2026-09-08T16:29:11.518Z",
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