CVE-2026-66004 ahujasid CVE debrief

Who should care

Defenders of systems using BlenderMCP should review and verify the presence of the vulnerable download_polyhaven_asset method, perform inventory checks, and monitor for suspicious API requests. This includes operators, platform administrators, vulnerability management teams, and security teams responsible for ensuring the security and integrity of affected systems.

Technical summary

CVE-2026-66004 is a path traversal vulnerability in BlenderMCP's download_polyhaven_asset method. Attackers can inject traversal sequences in API response include keys to write arbitrary files, potentially achieving persistent code execution via malicious paths like '../../.bashrc'. The vulnerability has a CVSS score of 6 and is classified as MEDIUM severity. Defenders should focus on verifying affected scope, restricting API access, and monitoring for suspicious patterns.

Defensive priority

Medium priority due to CVSS score of 6 and potential for code execution. Defenders should prioritize verification of affected scope, restrict API access, and implement compensating controls.

Recommended defensive actions

• Verify BlenderMCP version and apply commit 30a3308 or later
• Restrict API access to download_polyhaven_asset method
• Monitor API requests for suspicious patterns
• Perform inventory checks for affected systems
• Implement compensating controls for file system access
• Review and validate vendor remediation guidance
• Track exceptions and retest remediated assets

Evidence notes

Evidence is based on limited source detail from Vulncheck and NVD. Further verification is needed to confirm affected scope and validate vendor remediation. Defenders should verify the presence of vulnerable BlenderMCP deployments, review API access controls, and monitor for suspicious activity. Evidence limits may impact the accuracy of affected scope and remediation guidance.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.