CVE-2026-72691 (GCVE-0-2026-72691)

Vulnerability from cvelistv5 – Published: 2026-08-10 11:59 – Updated: 2026-08-10 18:22
VLAI
Title
OpenSignLabs opensignserver - Authentication Bypass
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-10 15:37 UTC
CWE
  • CWE-288 - Authentication Bypass Using an Alternate Path or Channel
Assigner
TuranSec CNA under the mitre root
CNA scorecard C 70/100 over 189 records in the last 180 days details
References
URL Tags
https://github.com/OpenSignLabs/OpenSign third-party-advisory
Impacted products
Vendor Product Version CPE status
OpenSignLabs opensignserver Affected: 0 , ≤ 2.37.0 (semver)
guessed Create a notification for this product.
Date Public
2026-08-10 12:00
Credits
Bobur Abdugafforov (Mahadsec)
Show details on NVD website
To clipboard 

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