CVE-2026-84289 (GCVE-0-2026-84289)

Vulnerability from cvelistv5 – Published: 2026-09-01 21:45 – Updated: 2026-09-01 21:45
VLAI
Title
NousResearch hermes-agent MCP Tool mcp_tool.py list_tools memory allocation
Summary
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.
CWE
  • CWE-789 - Uncontrolled Memory Allocation
  • CWE-400 - Resource Consumption
References
URL Tags
https://vuldb.com/vuln/397720 vdb-entrytechnical-description
https://vuldb.com/vuln/397720/cti signaturepermissions-required
https://vuldb.com/cve/CVE-2026-84289 third-party-advisory
https://vuldb.com/submit/882960 third-party-advisory
https://github.com/lche511/cve/blob/main/Hermes_M… exploit
Impacted products
Vendor Product Version CPE status
NousResearch hermes-agent Affected: 0.18.0
Affected: 0.18.1
Affected: 0.18.2
    cpe:2.3:a:nousresearch:hermes-agent:*:*:*:*:*:*:*:*
Create a notification for this product.
Show details on NVD website

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  "cveMetadata": {
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    "dateReserved": "2026-09-01T15:48:59.951Z",
    "dateUpdated": "2026-09-01T21:45:09.843Z",
    "state": "PUBLISHED"
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  }
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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