---
id: CVE-2026-108164
title: >-
  Open Source Social Network (OSSN) through 10.1 contains an insecure direct
  object reference vulnerability in components/OssnMessages/ossn_com.php that
  allows authenticated users to read other users' private message attachments
summary: >-
  Open Source Social Network (OSSN) through 10.1 contains an insecure direct
  object reference vulnerability in components/OssnMessages/ossn_com.php that
  allows authenticated users to read other users' private message attachments.
  Attackers…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-639
published: '2026-10-10'
updated: '2026-10-10'
sourceUpdated: '2026-10-10T14:16:37.663'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-108164'
references:
  - url: 'https://github.com/opensource-socialnetwork/opensource-socialnetwork'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/opensource-socialnetwork/opensource-socialnetwork/blob/48b53f5b95488187715b2d5b5ae46a993267f83d/components/OssnMessages/ossn_com.php#L149-L156
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/opensource-socialnetwork/opensource-socialnetwork/commit/2e9733d8eaafccdaef3d9b498348c8332e51f48b
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/opensource-socialnetwork/opensource-socialnetwork/issues/2641
    label: disclosure@vulncheck.com
  - url: 'https://hackmd.io/@leediay/ossn-idor-message-attachment'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/open-source-social-network-ossn-through-10.1-idor-via-message-attachment-route
    label: disclosure@vulncheck.com
tags:
  - nvd
ingestedAt: '2026-10-10T15:25:58.082Z'
---

## Overview

Open Source Social Network (OSSN) through 10.1 contains an insecure direct object reference vulnerability in components/OssnMessages/ossn_com.php that allows authenticated users to read other users' private message attachments. Attackers can request the /messages/attachment/{guid} route with sequential or guessed file GUIDs to retrieve attachments from private conversations without sender or recipient verification.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.