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TI-2026-56610 Aliases CVE-2026-82021GHSA-w9gw-vgmg-q67h

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

Priority MEDIUM 41CWE-494Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Passive
Attack complexity
High
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-494.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00339 27th percentileScored 2026-11-07
Fix Fixed hermes-agent (NousResearch): 0.19.0, 2026.7.20

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
NousResearchhermes-agent0.18.2 to before 0.19.0; 2026.7.7.2 to before 2026.7.200.19.0, 2026.7.20Patch availableCNA
  • hermes-agent VendorNousResearch Affected 0.18.2 to before 0.19.0; 2026.7.7.2 to before 2026.7.20 Fixed in 0.19.0, 2026.7.20 Patch available CNA

Remediation

  • Fix · CNA hermes-agent (NousResearch) Fixed in 0.19.0, 2026.7.20

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-82021
  2. 2026-10-03 Alias added: GHSA-w9gw-vgmg-q67h

References

Patch 2

Other 1

  • TI-2026-50258 Hermes Agent 0.18.2 - 0.21.0 RCE via git core.fsmonitor Config Injection CVSS 4.0HIGH 8.6
  • TI-2026-12325 NousResearch hermes-agent Live Webhook Endpoint base.py extract_media path traversal CVSS 4.0MEDIUM 6.9
  • TI-2026-08962 NousResearch hermes-agent Webhook Endpoint feishu.py _handle_webhook_request resource consumption CVSS 4.0MEDIUM 6.9
  • TI-2026-08959 NousResearch hermes-agent run_agent.py _compress_context injection CVSS 4.0MEDIUM 6.9
  • TI-2026-08958 NousResearch hermes-agent skills_tool.py skill_view injection CVSS 4.0MEDIUM 6.9
  • TI-2026-08218 NousResearch hermes-agent Environment Variable code_execution_tool.py execute_code sandbox CVSS 4.0MEDIUM 6.9
See all 44 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences