CVE-2026-72691 - Vulnerability Details - OpenCVE

An authentication bypass vulnerability in OpenSignLabs opensignserver through 2.37.0 allows an unauthenticated remote attacker to mint MASTER_KEY-signed file access tokens for arbitrary stored files via the getsignedurl Parse cloud function. The function skips its isAuthenticated check whenever any docId parameter is supplied, even one corresponding to no real document, allowing the authentication gate to be bypassed by supplying an arbitrary string as docId.

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		An authentication bypass vulnerability in OpenSignLabs opensignserver through 2.37.0 allows an unauthenticated remote attacker to mint MASTER_KEY-signed file access tokens for arbitrary stored files via the getsignedurl Parse cloud function. The function skips its isAuthenticated check whenever any docId parameter is supplied, even one corresponding to no real document, allowing the authentication gate to be bypassed by supplying an arbitrary string as docId.
Title		OpenSignLabs opensignserver - Authentication Bypass
Weaknesses		CWE-288
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: 2026-08-10T11:59:11.981Z

Updated: 2026-08-10T18:22:08.110Z

Reserved: 2026-08-10T11:55:39.471Z

Link: CVE-2026-72691

Vulnrichment

Updated: 2026-08-10T15:37:54.790Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

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

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