CVE-2026-116635
Improper limitation of a pathname to a restricted directory in the deployment status component of the AWS Serverless MCP Server
Improper limitation of a pathname to a restricted directory in the deployment status component of the AWS Serverless MCP Server (aws-serverless-mcp-server) before v0.2.1 might allow an actor who can influence the MCP agent to read the contents of JSON files outside the intended deployment status directory. Where write access has been enabled, to create or overwrite JSON files outside that directory. This issue is reachable through directory traversal sequences or an absolute path supplied in the project name input. To remediate this issue, users should upgrade to version v0.2.1.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: AMZNAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| aws-serverless-mcp-server AWS |
≥ 0; < 0.2.1 (affected, custom)
Other versions: unaffected |
CNA: AMZN |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 6.1 medium |
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N | CNA: AMZN |
| 4.0 / 6.9 medium |
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N | CNA: AMZN |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://pypi.org/project/awslabs.aws-serverless-mcp-server/0.2.1/CNA: AMZN · release-notes, patch
- https://aws.amazon.com/security/security-bulletins/2026-164-aws/CNA: AMZN · vendor-advisory
- https://github.com/awslabs/mcp/security/advisories/GHSA-r6mm-377j-qg8mCNA: AMZN · third-party-advisory
For agents and automation
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