CVE-2025-6854 in Langchain-Chatchat
Summary
by MITRE • 06/29/2025
A vulnerability classified as problematic was found in chatchat-space Langchain-Chatchat up to 0.3.1. This vulnerability affects unknown code of the file /v1/files?purpose=assistants. The manipulation leads to path traversal. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used.
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Analysis
by VulDB Data Team • 11/01/2025
The vulnerability identified as CVE-2025-6854 represents a critical path traversal issue within the chatchat-space Langchain-Chatchat framework version 0.3.1 and earlier. This security flaw resides in the file handling mechanism at the endpoint /v1/files?purpose=assistants, where improper input validation allows attackers to manipulate file paths and access unauthorized system resources. The vulnerability is particularly concerning as it enables remote exploitation without requiring local system access, making it accessible to attackers anywhere on the network. Path traversal vulnerabilities of this nature typically arise when applications fail to properly sanitize user-supplied input before using it in file system operations, creating opportunities for malicious actors to navigate beyond intended directories and potentially access sensitive files or execute arbitrary code.
The technical exploitation of this vulnerability follows established patterns described in CWE-22, which categorizes path traversal attacks as a fundamental weakness in input validation. Attackers can leverage this flaw by crafting malicious requests that include directory traversal sequences such as ../ or ..\ in the file path parameters. When the application processes these requests through the /v1/files endpoint with purpose=assistants, the inadequate validation allows the traversal to succeed, potentially enabling access to system files, configuration data, or other sensitive resources that should remain protected. The remote nature of the attack means that threat actors can initiate exploitation from external networks without requiring physical access to the target system, significantly increasing the attack surface and potential impact.
The operational impact of CVE-2025-6854 extends beyond simple unauthorized file access, as it can potentially lead to complete system compromise depending on the application's configuration and the privileges associated with the file access operations. An attacker who successfully exploits this vulnerability could gain access to sensitive data, potentially including user credentials, system configurations, or proprietary information stored within the application's file system. The disclosure of this exploit to the public increases the risk of widespread exploitation, as malicious actors can readily implement the attack without requiring advanced technical skills or specialized tools. Organizations using affected versions of Langchain-Chatchat must consider this vulnerability as a high-priority threat that could result in data breaches, system compromise, or other serious security incidents that could affect both operational integrity and regulatory compliance.
Mitigation strategies for CVE-2025-6854 should focus on immediate remediation through version updates to the Langchain-Chatchat framework, as well as implementing robust input validation mechanisms at the application level. Organizations should deploy web application firewalls and implement proper access controls to limit exposure of vulnerable endpoints, while also conducting thorough security audits to identify any additional path traversal vulnerabilities within their applications. The implementation of principle of least privilege access controls and regular security assessments aligns with established best practices from both CWE guidelines and ATT&CK framework recommendations for defending against file system traversal attacks. Additionally, organizations should consider implementing automated monitoring and alerting systems to detect suspicious file access patterns that might indicate exploitation attempts, as well as maintaining comprehensive backup and recovery procedures to ensure business continuity in case of successful attacks.