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TI-2026-50929 Aliases CVE-2026-72691GHSA-9g58-36q9-g7mq

OpenSignLabs opensignserver - Authentication Bypass

Priority MEDIUM 40CWE-288Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-288.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00647 51st percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OpenSignLabsopensignserverup to 2.37.0—No fix listedCNA
  • opensignserver VendorOpenSignLabs Affected up to 2.37.0 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-72691
  2. 2026-10-03 Alias added: GHSA-9g58-36q9-g7mq
  3. 2026-10-19 EPSS moved to the 50th–90th percentile

References

Advisory 1

  • TI-2026-62535 OpenSign through 2.41.3 Information Disclosure via getDocument CVSS 4.0HIGH 8.7
  • TI-2026-50926 OpenSignLabs opensignserver - Missing Authentication for Critical Function CVSS 3.1HIGH 7.5
  • TI-2026-50807 OpenSignLabs OpenSign - Information Disclosure CVSS 3.1HIGH 7.5
  • TI-2026-50804 OpenSignLabs OpenSign - Insecure Direct Object Reference CVSS 3.1HIGH 7.5
  • TI-2026-50802 OpenSignLabs OpenSign - Insecure Direct Object Reference CVSS 3.1HIGH 7.5
  • TI-2026-50930 OpenSignLabs opensignserver - Missing Authorization CVSS 3.1HIGH 7.5
See all 9 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences