CVE-2026-9354

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.

CVSS v3 6.5 MEDIUM
CVSS v2.0 6.4 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

6.4^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:N/I:P/A:P

Exploitability : 10.0 / Impact : 4.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://gist.github.com/YLChen-007/e90fb38ac03284176bae49898a3a46a4
https://vuldb.com/submit/812226
https://vuldb.com/vuln/365317
https://vuldb.com/vuln/365317/cti

Configurations

No configuration.

History

24 May 2026, 05:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-24 05:16

Updated : 2026-05-26 19:50

NVD link : CVE-2026-9354

Mitre link : CVE-2026-9354

CVE.ORG link : CVE-2026-9354

JSON object : View

Products Affected

No product.

CWE

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

CWE-116

Improper Encoding or Escaping of Output

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