CVE-2026-49986
Received
Received - Intake
Cortex MCP Server Arbitrary Code Execution via Environment Variable
Vulnerability report for CVE-2026-49986, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-14
Last updated on: 2026-08-14
Assigner: GitHub, Inc.
Description
Description
The Cortex MCP server (`neuro-cortex-memory`), a cross-platform persistent memory MCP, prior to version 3.17.1 treats the `CLAUDE_PROJECT_DIR` environment variable — automatically set by Claude Code to the currently open project directory — as a trusted Cortex developer checkout. When the `open_visualization` tool is invoked, `_find_dev_source()` resolves the user's active project directory as a candidate Cortex source root. The only validation performed by `_is_cortex_root()` is a check for the presence of an `mcp_server/` subdirectory and a `ui/unified-viz.html` file. An attacker who places these two marker files in a malicious repository can cause Cortex to execute an arbitrary `mcp_server/server/visualize_bootstrap.py` from that directory via `subprocess.run([sys.executable, ...])`, achieving code execution with the privileges of the victim's local user process. Version 3.17.1 fixes the issue.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| cortex | mcp_server | to 3.17.1 (exc) |
| cdeust | neuro-cortex-memory | to 3.17.0 (inc) |
| cdeust | neuro-cortex-memory | 3.18.0 |
| cdeust | cortex | 3.17.1 |
| cdeust | cortex | 3.18.0 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-829 | The product imports, requires, or includes executable functionality (such as a library) from a source that is outside of the intended control sphere. |
