Vulnerability-Lookup

CVE-2026-72688 (GCVE-0-2026-72688)

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

Title

OpenSignLabs opensignserver - Missing Authentication for Critical Function

Summary

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.

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 15:51 UTC

CWE

CWE-306 - Missing Authentication for Critical Function

Assigner

TuranSec redhat root

References

1 reference

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

Impacted products

1 product

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

Date Public

2026-08-10 12:00

Credits

Bobur Abdugafforov (Mahadsec)

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-72688

Vulnerability from fkie_nvd - Published: 2026-08-10 13:20 - Updated: 2026-08-26 17:36

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Summary

References

	URL	Tags
	309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c	https://github.com/OpenSignLabs/OpenSign

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "affected",
          "product": "opensignserver",
          "vendor": "OpenSignLabs",
          "versions": [
            {
              "lessThanOrEqual": "2.37.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
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    }
  ],
  "id": "CVE-2026-72688",
  "lastModified": "2026-08-26T17:36:16.900",
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          "privilegesRequired": "NONE",
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GHSA-JPPP-J33J-6M5Q

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

Details

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-72688"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-306"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T13:20:38Z",
    "severity": "HIGH"
  },
  "details": "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.",
  "id": "GHSA-jppp-j33j-6m5q",
  "modified": "2026-08-10T15:33:51Z",
  "published": "2026-08-10T15:33:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72688"
    },
    {
      "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"
    }
  ]
}

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2026-72688 (GCVE-0-2026-72688)

FKIE_CVE-2026-72688

GHSA-JPPP-J33J-6M5Q

Tags

Sightings

Nomenclature

Related by attack behaviour