CVE-2026-82021

Hermes Agent 0.18.2 prior to 0.19.0 contains a supply chain vulnerability in its bundled MCP catalog that allows a remote attacker to execute arbitrary code by compromising a third-party upstream repository referenced via a mutable branch rather than a pinned commit SHA. An attacker who compromises the upstream repository can propagate malicious code to every host that installs the affected catalog entry, with no further action required by the operator.

CVSS v3 8.3 HIGH

8.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/NousResearch/hermes-agent/commit/9df5f879b4a5925c0f8f947e7e16ed8e845932c3
https://github.com/NousResearch/hermes-agent/pull/64463
https://github.com/NousResearch/hermes-agent/releases/tag/v2026.7.20
https://www.vulncheck.com/advisories/hermes-agent-mcp-catalog-supply-chain-rce-via-mutable-branch-reference

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 20:20

Updated : 2026-09-08 20:23

NVD link : CVE-2026-82021

Mitre link : CVE-2026-82021

CVE.ORG link : CVE-2026-82021

JSON object : View

Products Affected

No product.

CWE

CWE-494

Download of Code Without Integrity Check

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