CVE-2026-79743 samanhappy CVE debrief

Who should care

Defenders responsible for MCPHub deployments should assess exposure and prioritize patching to version 0.12.13 or later. They should also verify the integrity of MCPB files and monitor for suspicious activity. This includes reviewing compensating controls for exposed systems while remediation is scheduled and verified, and checking relevant monitoring, detection, and logs for exposed assets that need extra review. Additionally, defenders should track and

Why it matters

CVE-2026-79743 is a vulnerability in MCPHub that allows an attacker to extract files to an arbitrary location on the file system and potentially delete arbitrary directories. Defenders should prioritize patching to version 0.12.13 or later and verify the integrity of MCPB files.

• Potential for arbitrary file extraction and directory deletion
• Need for verification of MCPB file integrity
• Potential for exploitation requires further verification

Technical summary

The MCPHub File Upload Handler extracts a ZIP file and reads manifest.json from it. The name field in the manifest is directly concatenated into a file path without any sanitization or path traversal character validation, allowing an attacker to craft a malicious MCPB file to extract files to an arbitrary location on the file system and potentially delete arbitrary directories. This issue has been patched in version 0.12.13. The vulnerability allows for potential security breaches and data tampering. Defenders should prioritize patching to version 0.12.13 or later and verify the integrity of MCPB files.

Defensive priority

Defenders should prioritize patching to version 0.12.13 or later and verify the integrity of MCPB files.

Recommended defensive actions

• Patch to version 0.12.13 or later
• Verify the integrity of MCPB files
• Monitor for suspicious activity
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability allows an attacker to extract files to an arbitrary location on the file system and potentially delete arbitrary directories by crafting a malicious MCPB file with a specially designed manifest.name field.

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.