Description
A vulnerability was detected in NousResearch hermes-agent up to 2026.4.16. The affected element is an unknown function of the component Slack Agent/Mattermost Agent. The manipulation of the argument format_message results in escaping of output. The attack can be executed remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| NousResearch | hermes-agent | 2026.4.0, 2026.4.1, 2026.4.2, 2026.4.3, 2026.4.4, 2026.4.5, 2026.4.6, 2026.4.7, 2026.4.8, 2026.4.9, 2026.4.10, 2026.4.11, 2026.4.12, 2026.4.13, 2026.4.14, 2026.4.15, 2026.4.16 | — |
References
- VDB-365317 | NousResearch hermes-agent Slack Agent/Mattermost Agent escape output vdb-entry technical-description
- VDB-365317 | CTI Indicators (IOB, IOC, IOA) signature permissions-required
- Submit #812226 | NousResearch hermes-agent 2026.4.16 Improper Encoding or Escaping of Output (CWE-116) third-party-advisory
- https://gist.github.com/YLChen-007/e90fb38ac03284176bae49898a3a46a4 exploit