CVE-2026-115845 Incomplete validation in the run_script Python sandbox in AWS MCP Server
Medium 5.3
Published
Updated
Check this codebase for CVE-2026-115845 and fix it if it is affected.
What it is: CVE-2026-115845 is a medium-severity vulnerability in AWS MCP Server, published on 23 Oct 2026.
Exploitation: There is no known exploitation of CVE-2026-115845 in the wild and no public exploit code.
Affected product: AWS MCP Server. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2026-115845/ (Markdown: https://insights.sbomify.com/CVE-2026-115845/index.md)
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-115845?
CVE-2026-115845 is a medium-severity vulnerability in AWS MCP Server, published on 23 Oct 2026.
Official description
An incomplete list of disallowed inputs in the Python code validator of the run_script tool in AWS MCP Server might allow an authenticated remote user to execute arbitrary code within their own isolated session environment via a crafted script.
AWS fixed this issue service-side. No customer action is required.
Weakness: CWE-184
Which versions are affected by CVE-2026-115845?
How do I fix CVE-2026-115845?
No fix has been published for CVE-2026-115845 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-115845 being exploited?
There is no known exploitation of CVE-2026-115845 in the wild and no public exploit code.
Sources
Also known as GHSA-jmwp-36mq-x645.