CVE-2025-49596 in the critical feed json
MCP Inspector proxy server lacks authentication between the Inspector client and proxy
published last yr. modified 4mo ago also GHSA-7f8r-222p-6f5g , EUVD-2025-20870
- cvss
- 9.4
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 39.9%
- EPSS 39.9% chance of exploitation in 30 days, percentile 98%
- public exploits
- 0
- none known, plus a Nuclei check
Summary
The MCP inspector is a developer tool for testing and debugging MCP servers. Versions of MCP Inspector below 0.14.1 are vulnerable to remote code execution due to lack of authentication between the Inspector client and proxy, allowing unauthenticated requests to launch MCP commands over stdio. Users should immediately upgrade to version 0.14.1 or later to address these vulnerabilities.
Patch / fix
Is CVE-2025-49596 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- last yr.
Exploit prediction
39.93% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- Nuclei template MCP Inspector < 0.14.0 UnauthenticatedRemote Code Execution nuclei detection template
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
| CNA | 4.0 | 9.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @modelcontextprotocol/inspector | <0.14.1 |
0.14.1 |
Affected products
- modelcontextprotocol inspector
Classification
- Weakness
-
- CWE-306 Missing Authentication for Critical Functionality
References
-
github.com
/modelcontextprotocol/inspector/commit/50df0e1ec488f3983740b4d28d2a968f12eb8979
web
-
github.com
/modelcontextprotocol/inspector/security/advisories/GHSA-7f8r-222p-6f5g
web
-
thenewstack.io
/mcp-vulnerability-exposes-the-ai-untrusted-code-crisis
web
-
oligo.security
/blog/critical-rce-vulnerability-in-anthropic-mcp-inspector-cve-2025-49596
web
-
nvd.nist.gov
/vuln/detail/CVE-2025-49596
advisory
-
github.com
/modelcontextprotocol/inspector
package
Sources
- CVE List CVE-2025-49596
- GitHub Advisory GHSA-7f8r-222p-6f5g
- NVD CVE-2025-49596
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