NousResearch hermes-agent up to 0.18.2 ACP Prompt Workflow acp_adapter/session.py HermesACPAgent.prompt denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.9$0-$5k1.34+

Summaryinfo

A vulnerability was found in NousResearch hermes-agent up to 0.18.2. It has been rated as problematic. This vulnerability affects the function HermesACPAgent.prompt of the file acp_adapter/session.py of the component ACP Prompt Workflow. Performing a manipulation results in denial of service. This vulnerability is cataloged as CVE-2026-84288. 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 problematic has been found in NousResearch hermes-agent up to 0.18.2. This affects the function HermesACPAgent.prompt of the file acp_adapter/session.py of the component ACP Prompt Workflow. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-84288. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details and a public exploit are known. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

The exploit is shared for download at 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.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 3.9

VulDB Base Score: 4.3
VulDB Temp Score: 3.9
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: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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

09/01/2026 Advisory disclosed
09/01/2026 +0 days VulDB entry created
09/01/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2026-84288 (🔒)
GCVE (CVE): GCVE-0-2026-84288
GCVE (VulDB): GCVE-100-397719
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 09/01/2026 17:53
Changes: 09/01/2026 17:53 (56), 09/01/2026 17:54 (1)
Complete: 🔍
Submitter: hackerguopeng
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #882873: NousResearch hermes-agent 0.18.2 Denial of Service (by hackerguopeng)

Be aware that VulDB is the high quality source for vulnerability data.

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