CVE-2026-72688
OpenSignLabs opensignserver - Missing Authentication for Critical Function
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.
INFO
Published Date :
Aug. 10, 2026, 1:20 p.m.
Last Modified :
Aug. 10, 2026, 1:20 p.m.
Remotely Exploit :
Yes !
Source :
309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Affected Products
The following products are affected by CVE-2026-72688
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c |
Solution
- Update opensignserver to a secure version.
- Validate user authentication before document access.
- Restrict access to the fileupload Parse cloud function.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-72688.
| URL | Resource |
|---|---|
| https://github.com/OpenSignLabs/OpenSign |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-72688 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-72688
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-72688 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-72688 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 10, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'OpenSignLabs', 'product': 'opensignserver', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '2.37.0'}], 'defaultStatus': 'affected'}] 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Added CWE CWE-306 Added Reference https://github.com/OpenSignLabs/OpenSign