CVE-2026-16496

HIGH

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

Title source: cna

Description

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.

References (1)

Core 1

Core References

https://discuss.hashicorp.com/t/hcsec-2026-23-multiple-vulnerabilities-impacting-hashicorp-terraform-mcp-server/77606

Scores

CVSS v3 8.9

EPSS 0.0027

EPSS Percentile 19.4%

Attack Vector NETWORK

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

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact total

Details

CWE

CWE-384

Status published

Products (1)

HashiCorp/Tooling 0.3.0 - 1.1.0

Published Jul 28, 2026

Tracked Since Jul 29, 2026