nesquena hermes-webui up to 0.51.442 Conversation /api/session authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k2.65-

Summaryinfo

A vulnerability classified as problematic has been found in nesquena hermes-webui up to 0.51.442. Impacted is an unknown function of the file /api/session of the component Conversation Handler. This manipulation causes authorization. This vulnerability is handled as CVE-2026-55197. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in nesquena hermes-webui up to 0.51.442 and classified as problematic. Affected by this vulnerability is some unknown processing of the file /api/session of the component Conversation Handler. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. As an impact it is known to affect confidentiality. The summary by CVE is:

Hermes WebUI before 0.51.443 contains a broken access control vulnerability in the /api/session endpoint that allows authenticated users to disclose cross-profile session transcripts. Attackers can bypass profile boundary checks by directly querying session IDs belonging to other profiles via GET /api/session?session_id=&messages=1 to retrieve unauthorized conversation transcripts and metadata.

The weakness was released by Chia Min Jun Lennon. It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-55197 since 06/16/2026. The exploitation appears to be easy. The attack can be launched remotely. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 0.51.443 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-37778). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Authorization
CWE: CWE-639 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: hermes-webui 0.51.443

Timelineinfo

06/16/2026 CVE reserved
06/17/2026 +1 days Advisory disclosed
06/17/2026 +0 days VulDB entry created
06/18/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Researcher: Chia Min Jun Lennon
Status: Confirmed

CVE: CVE-2026-55197 (🔒)
GCVE (CVE): GCVE-0-2026-55197
GCVE (VulDB): GCVE-100-372091
EUVD: 🔒

Entryinfo

Created: 06/17/2026 20:46
Updated: 06/18/2026 00:00
Changes: 06/17/2026 20:46 (77), 06/18/2026 00:00 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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