CVE-2026-82021

Hermes Agent 0.18.2 < 0.19.0 MCP Catalog Supply Chain RCE via Mutable Branch Reference

Published: Aug 28, 2026Updated: Sep 8, 2026 Sources: CVE List NVDCWE-494

8.3HIGH

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:HAttack Complexity

High

PR:NPrivileges Required

None

UI:RUser Interaction

Required

Scope

S:CScope

Changed

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-494

Affected Products

NousResearch

commercialaka hermes-agent

hermes-agentMixed

AI / ML / ai-agent-tooling

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Initial Access

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References

https://github.com/NousResearch/hermes-agent/releases/tag/v2026.7.20

github.com

https://github.com/NousResearch/hermes-agent/pull/64463

github.com

https://github.com/NousResearch/hermes-agent/commit/9df5f879b4a5925c0f8f947e7e16ed8e845932c3

github.com

and 1 more references View all →

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