Vulnerability Description
A vulnerability was found in NousResearch hermes-agent up to 0.18.2. This vulnerability affects the function list_tools of the file tools/mcp_tool.py of the component MCP Tool. Performing a manipulation results in uncontrolled memory allocation. It is possible to initiate the attack remotely. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/lche511/cve/blob/main/Hermes_MCP_Tool_Resource_Amplification_
- https://vuldb.com/cve/CVE-2026-84289
- https://vuldb.com/submit/882960
- https://vuldb.com/vuln/397720
- https://vuldb.com/vuln/397720/cti
FAQ
What is CVE-2026-84289?
CVE-2026-84289 is a vulnerability with a CVSS score of 4.3 (MEDIUM). A vulnerability was found in NousResearch hermes-agent up to 0.18.2. This vulnerability affects the function list_tools of the file tools/mcp_tool.py of the component MCP Tool. Performing a manipulati...
How severe is CVE-2026-84289?
CVE-2026-84289 has been rated MEDIUM with a CVSS base score of 4.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-84289?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.