Vulnerability-Lookup

GHSA-9G58-36Q9-G7MQ

Vulnerability from github – Published: 2026-08-10 15:33 – Updated: 2026-08-10 15:33

Details

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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-72691"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-288"
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    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T13:20:39Z",
    "severity": "HIGH"
  },
  "details": "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.",
  "id": "GHSA-9g58-36q9-g7mq",
  "modified": "2026-08-10T15:33:51Z",
  "published": "2026-08-10T15:33:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72691"
    },
    {
      "type": "WEB",
      "url": "https://github.com/OpenSignLabs/OpenSign"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

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

Vulnerability from cvelistv5 – Published: 2026-08-10 11:59 – Updated: 2026-08-10 18:22

Title

OpenSignLabs opensignserver - Authentication Bypass

Summary

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

References

1 reference

URL	Tags
https://github.com/OpenSignLabs/OpenSign	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
OpenSignLabs	opensignserver	Affected: 0 , ≤ 2.37.0 (semver)

Date Public

2026-08-10 12:00

Credits

Bobur Abdugafforov (Mahadsec)

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                  },
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                  }
                ],
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                "timestamp": "2026-08-10T15:37:46.009148Z",
                "version": "2.0.3"
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-9G58-36Q9-G7MQ

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

Tags

Sightings

Nomenclature