CVE-2026-9354CWE-116CWE-74
NousResearch hermes-agent Slack Agent/Mattermost Agent escape output
Medium · published May 24, 2026
What it is
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.
The record
Technical detail
- CVSS v4.0
- 6.9 · MEDIUM
- Vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
- EPSS
- 0.00571 · 46.5th percentile
- Weaknesses
- CWE-116 · Improper Encoding or Escaping of Output; CWE-74 · Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
- Published
- 2026-05-24T04:15Z
EPSS history
Timeline