NousResearch hermes-agent 2026.4.23 agent/prompt_builder.py _scan_context_content injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in NousResearch hermes-agent 2026.4.23. This affects the function _scan_context_content of the file agent/prompt_builder.py. This manipulation causes injection. The identification of this vulnerability is CVE-2026-9366. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. The vendor was contacted early about this disclosure but did not respond in any way.

Detailsinfo

A vulnerability classified as critical was found in NousResearch hermes-agent 2026.4.23. Affected by this vulnerability is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation with an unknown input leads to a injection vulnerability. The CWE definition for the vulnerability is CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability.

The advisory is shared at gist.github.com. This vulnerability is known as CVE-2026-9366. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details and also a public exploit are known. MITRE ATT&CK project uses the attack technique T1055 for this issue.

It is possible to download the exploit at gist.github.com. It is declared as proof-of-concept. The vendor was contacted early about this disclosure but did not respond in any way.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-31580). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.6

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Injection
CWE: CWE-74 / CWE-707 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

05/23/2026 Advisory disclosed
05/23/2026 +0 days VulDB entry created
05/25/2026 +2 days VulDB entry last update

Sourcesinfo

Advisory: gist.github.com
Status: Not defined

CVE: CVE-2026-9366 (🔒)
GCVE (CVE): GCVE-0-2026-9366
GCVE (VulDB): GCVE-100-365329
EUVD: 🔒
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 05/23/2026 12:38
Updated: 05/25/2026 08:00
Changes: 05/23/2026 12:38 (56), 05/25/2026 08:00 (1)
Complete: 🔍
Submitter: Eric-i
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #812227: NousResearch hermes-agent 2026.4.23 Injection (CWE-74) (by Eric-i)

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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