CVE-2026-72688
OpenSignLabs opensignserver - Missing Authentication for Critical Function
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-306 |
| Vendor | opensignlabs |
| Product | opensignserver |
| Published | Aug 10, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
OpenSignLabs / opensignserver
0 ≤ 2.37.0
Credits
Bobur Abdugafforov (Mahadsec)