CVE-2026-72688 - Vulnerability Details - OpenCVE

A missing authentication vulnerability in OpenSignLabs opensignserver through 2.37.0 allows an unauthenticated remote attacker to read arbitrary stored documents via the fileupload Parse cloud function. The function mints MASTER_KEY-signed file access tokens for any caller-supplied URL without performing any session check, defeating the only access control protecting stored contract files.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

No data.

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products

References

Link	Providers
https://github.com/OpenSignLabs/OpenSign

History

Mon, 10 Aug 2026 19:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 10 Aug 2026 12:30:00 +0000

Type	Values Removed	Values Added
Description		A missing authentication vulnerability in OpenSignLabs opensignserver through 2.37.0 allows an unauthenticated remote attacker to read arbitrary stored documents via the fileupload Parse cloud function. The function mints MASTER_KEY-signed file access tokens for any caller-supplied URL without performing any session check, defeating the only access control protecting stored contract files.
Title		OpenSignLabs opensignserver - Missing Authentication for Critical Function
Weaknesses		CWE-306
References		https://github.com/OpenSignLabs/OpenSign
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}`

MITRE

Status: PUBLISHED

Assigner: TuranSec

Published: 2026-08-10T11:59:02.770Z

Updated: 2026-08-10T18:22:30.882Z

Reserved: 2026-08-10T11:55:39.470Z

Link: CVE-2026-72688

Vulnrichment

Updated: 2026-08-10T15:51:49.926Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-08-10T19:00:04Z

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