Vulnerability-Lookup

CVE-2026-16496 (GCVE-0-2026-16496)

Vulnerability from cvelistv5 – Published: 2026-07-28 17:57 – Updated: 2026-07-28 18:43

Title

terraform-mcp-server vulnerable to cross-user credential inheritance if an MCP session ID is obtained by another user

Summary

The terraform-mcp-server before version 1.1.0 is vulnerable to an authorization bypass in the streamable-HTTP stateful transport mode that may allow a user who obtains another user's MCP session ID to have their tool calls executed using that user's Terraform credentials. This vulnerability, CVE-2026-16496, is fixed in terraform-mcp-server 1.1.0.

Severity

8.9 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-384 - Session Fixation

Assigner

HashiCorp

References

1 reference

URL	Tags
https://discuss.hashicorp.com/t/hcsec-2026-23-mul…

Impacted products

1 product

Vendor	Product	Version
HashiCorp	Tooling	Affected: 0.3.0 , < 1.1.0 (semver)

Credits

This issue was reported to HashiCorp by Juan Pablo Martinez Kuhn of Coinspect.

Show details on NVD website

JSON

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GHSA-4CRW-P722-VR7H

Vulnerability from github – Published: 2026-07-28 21:31 – Updated: 2026-07-28 21:31

Details

Severity

8.9 (High)


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

Show details on source website

JSON

To clipboard

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  "affected": [],
  "aliases": [
    "CVE-2026-16496"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-384"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-28T19:17:31Z",
    "severity": "HIGH"
  },
  "details": "The terraform-mcp-server before version 1.1.0 is vulnerable to an authorization bypass in the streamable-HTTP stateful transport mode that may allow a user who obtains another user\u0027s MCP session ID to have their tool calls executed using that user\u0027s Terraform credentials. This vulnerability, CVE-2026-16496, is fixed in terraform-mcp-server 1.1.0.",
  "id": "GHSA-4crw-p722-vr7h",
  "modified": "2026-07-28T21:31:31Z",
  "published": "2026-07-28T21:31:31Z",
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    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-16496"
    },
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      "url": "https://discuss.hashicorp.com/t/hcsec-2026-23-multiple-vulnerabilities-impacting-hashicorp-terraform-mcp-server/77606"
    }
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  "schema_version": "1.4.0",
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      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L",
      "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.

Action not permitted

CVE-2026-16496 (GCVE-0-2026-16496)

GHSA-4CRW-P722-VR7H

Tags

Sightings

Nomenclature