CVE-2026-49986
CVE-2026-49986 is a CWE-829 vulnerability in neuro-cortex-memory. O3 Security confirms whether CVE-2026-49986 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cortex has Untrusted Project Bootstrap Code Execution via `CLAUDE_PROJECT_DIR`
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
neuro-cortex-memoryReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | neuro-cortex-memory | all versions | 3.18.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for neuro-cortex-memory. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update neuro-cortex-memory to 3.18.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-49986 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-49986 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-49986. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-49986 in your dependencies?
O3 detects CVE-2026-49986 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.