CVE-2026-18953 Improper limitation of a pathname to a restricted directory in aws-transform-mcp-server
An attacker can write arbitrary files outside the intended directory via the savePath parameter in the AWS Transform MCP server.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-18953?
CVE-2026-18953 is a medium-severity path traversal vulnerability in aws-transform-mcp-server, published on 5 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Improper limitation of a pathname to a restricted directory in the get_resource tool in Amazon awslabs.aws-transform-mcp-server 0.1.0 through 0.1.4 might allow a context-dependent actor to write arbitrary files outside the intended working directory via the savePath parameter.
To remediate this issue, users should upgrade to version 0.1.5 or later.
Weakness: CWE-22
Which versions are affected by CVE-2026-18953?
It affects 1 product.
Products include Amazon Aws Transform Mcp Server.
How do I fix CVE-2026-18953?
No fix has been published for CVE-2026-18953 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-18953 being exploited?
There is no known exploitation of CVE-2026-18953 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.