CVE-2026-108164

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/opensource-socialnetwork/opensource-socialnetwork
https://github.com/opensource-socialnetwork/opensource-socialnetwork/blob/48b53f5b95488187715b2d5b5ae46a993267f83d/components/OssnMessages/ossn_com.php#L149-L156
https://github.com/opensource-socialnetwork/opensource-socialnetwork/commit/2e9733d8eaafccdaef3d9b498348c8332e51f48b
https://github.com/opensource-socialnetwork/opensource-socialnetwork/issues/2641
https://hackmd.io/@leediay/ossn-idor-message-attachment
https://www.vulncheck.com/advisories/open-source-social-network-ossn-through-10.1-idor-via-message-attachment-route

Configurations

No configuration.

History

10 Oct 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-10 14:16

Updated : 2026-10-16 19:18

NVD link : CVE-2026-108164

Mitre link : CVE-2026-108164

CVE.ORG link : CVE-2026-108164

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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