---
id: "CVE-2025-65200"
kind: "vulnerability"
aliases: ["CVE-2025-65200"]
title: "LocalStack: crafted CloudFormation template URL runs code in container"
severity: "unknown"
cvss: null
epss: 0.00181
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["aws-emulation", "ci", "docker", "infrastructure", "localstack"]
not_affected_if: ["default-config"]
published_at: "2026-10-22T19:17:32+00:00"
first_seen_at: "2026-10-23T21:57:31+00:00"
updated_at: "2026-10-25T05:00:23+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-65200", "first_seen_at": "2026-10-23T21:57:31+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2025-65200", "first_seen_at": "2026-10-24T07:15:51+00:00"}]
---

# LocalStack: crafted CloudFormation template URL runs code in container

LocalStack 4.9.2 fetches a CloudFormation template from a URL passed to its deploy endpoint, and the fetched content is executed inside the Docker container. An attacker who controls a web-hosted file and can submit a deploy request can run arbitrary code in that container.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `localstack --version` or check the image tag in use and confirm whether it is `4.9.2`
- Check whether the `_localstack/cloudformation/deploy` endpoint is reachable from untrusted networks

## Timeline

- 2026-10-23T21:57:31+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2025-65200
- 2026-10-24T07:15:51+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2025-65200

## From the sources

An issue was discovered in localstack 4.9.2 allowing attackers to execute arbitrary code via crafted content hosted on a web-accessable URL and when passed said URL in the the templateURL to the _localstack/cloudformation/deploy endpoint, the hosted content can get executed in the context of the docker container.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_