# CVE-2026-16496 — HashiCorp Tooling

> As of 2026-07-28, CVE-2026-16496 is a HIGH-severity vulnerability in HashiCorp Tooling, CVSS v3.1 8.9, EPSS 0.3% (27.1th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-16496, most recently “August 2026 Patch Roundup: 11 Critical/High CVEs in Veeam VSPC (CVE-2026-58073, CVSS 9.5), HashiCorp Terraform MCP Server (CVE-2026-16498, CVSS 10.0), and Django”.

**Last updated:** 2026-07-28

## What is CVE-2026-16496?

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.

The record classifies CVE-2026-16496 under weakness class [CWE-384](https://intel.threadlinqs.com/cwe/CWE-384). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 74 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.9 — HIGH (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L`)
- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 27.1% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.5/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-07-28

## Is CVE-2026-16496 being exploited?

It currently carries a trending score of 23 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [HashiCorp](https://intel.threadlinqs.com/vendors/hashicorp): Tooling

## How to fix CVE-2026-16496

No vendor patch reference has been recorded for CVE-2026-16496 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-16496

1 tracked threat in the Threadlinqs corpus references CVE-2026-16496, either in the campaign’s CVE list or as an indicator on the campaign record.

- [August 2026 Patch Roundup: 11 Critical/High CVEs in Veeam VSPC (CVE-2026-58073, CVSS 9.5), HashiCorp Terraform MCP Server (CVE-2026-16498, CVSS 10.0), and Django](https://intel.threadlinqs.com/threat/TL-2026-1891) — CRITICAL · 2026-08-05

## Sources

Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on 2026-10-10.

**Other references**

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

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-16496
Full detection coverage and IOCs for threats exploiting CVE-2026-16496 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp