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CVE-2026-49986 (GCVE-0-2026-49986)

Vulnerability from cvelistv5 – Published: 2026-08-14 16:21 – Updated: 2026-08-17 19:35
VLAI
Title
Cortex has Untrusted Project Bootstrap Code Execution via `CLAUDE_PROJECT_DIR`
Summary
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.
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-17 19:35 UTC
CWE
  • CWE-829 - Inclusion of Functionality from Untrusted Control Sphere
Impacted products
Vendor Product Version CPE status
cdeust Cortex Affected: < 3.17.1
guessed Create a notification for this product.
Show details on NVD website

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