CVE-2026-16496 terraform-mcp-server vulnerable to cross-user credential inheritance if an MCP session ID is obtained by another user
Attackers with another user's session ID can execute Terraform commands using that user's credentials in the streamable-HTTP mode.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-16496?
CVE-2026-16496 is a high-severity authentication bypass vulnerability in HashiCorp Tooling, published on 28 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-384
Which versions are affected by CVE-2026-16496?
1 open source package ship an affected version, including consul.
| Package | Affected | Fixed in |
|---|---|---|
consul Bitnami | From 0.3.0 | 1.1.0 |
How do I fix CVE-2026-16496?
Upgrade consul to 1.1.0 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-16496 being exploited?
There is no known exploitation of CVE-2026-16496 in the wild and no public exploit code.
Sources
Also known as BIT-consul-2026-16496, GHSA-4crw-p722-vr7h.