danny-avila LibreChat up to 0.8.3-rc1 Model Context Protocol information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.47

Summaryinfo

A vulnerability classified as problematic was found in danny-avila LibreChat up to 0.8.3-rc1. This affects an unknown function of the component Model Context Protocol. Such manipulation leads to information disclosure. This vulnerability is uniquely identified as CVE-2026-31951. The attack can be launched remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in danny-avila LibreChat up to 0.8.3-rc1. It has been rated as problematic. Affected by this issue is an unknown function of the component Model Context Protocol. The manipulation with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. CVE summarizes:

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc1 through 0.8.3-rc1, user-created MCP (Model Context Protocol) servers can include arbitrary HTTP headers that undergo credential placeholder substitution. An attacker can create a malicious MCP server with headers containing `{{LIBRECHAT_OPENID_ACCESS_TOKEN}}` (and others), causing victims who call tools on that server to have their OAuth tokens exfiltrated. Version 0.8.3-rc2 fixes the issue.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-31951 since 03/10/2026. The exploitation is known to be easy. The attack may be launched remotely. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1592.

Upgrading to version 0.8.3-rc2 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.1

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.8
CNA Vector (GitHub_M): 🔒

CVSSv2info

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

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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: LibreChat 0.8.3-rc2

Timelineinfo

03/10/2026 CVE reserved
03/27/2026 +17 days Advisory disclosed
03/27/2026 +0 days VulDB entry created
03/27/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-pmw7-gqwj-f954
Status: Confirmed

CVE: CVE-2026-31951 (🔒)
GCVE (CVE): GCVE-0-2026-31951
GCVE (VulDB): GCVE-100-354032

Entryinfo

Created: 03/27/2026 23:44
Changes: 03/27/2026 23:44 (66)
Complete: 🔍
Cache ID: 216:DCC:103

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