nezha vulnerability

Nezha from 2.1.0 before 2.3.15 contains a host header injection vulnerability in mintTransferTool that builds fs.download_url and fs.upload_url transfer URLs from the unvalidated Host header. Attackers who control the Host header seen on a victim's MCP request can redirect file uploads or capture one-time download tokens and replay them to exfiltrate files.

Published 16 Oct 2026Updated 21 Oct 20265 sources
CVSS 6.3

What happened

Nezha from 2.1.0 before 2.3.15 contains a host header injection vulnerability in mintTransferTool that builds fs.download_url and fs.upload_url transfer URLs from the unvalidated Host header. Attackers who control the Host header seen on a victim's MCP request can redirect file uploads or capture one-time download tokens and replay them to exfiltrate files.

Affected versions

nezha: 2.1.0 through before 2.3.15 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.