CVE-2026-6597: Langflow-AI Information Disclosure Flaw

CVE-2026-6597 Overview

A credential storage vulnerability has been identified in langflow-ai Langflow versions up to 1.8.3. The vulnerability affects the remove_api_keys and has_api_terms functions within src/backend/base/langflow/api/utils/core.py, which is part of the Flow Using API component. This flaw results in unprotected storage of credentials, allowing attackers to potentially access sensitive API keys and credentials stored by the application.

Critical Impact

Remote attackers with high privileges can exploit this vulnerability to access unprotected credential storage, potentially exposing API keys and sensitive authentication data used within Langflow workflows.

Affected Products

• langflow-ai Langflow versions up to and including 1.8.3
• Systems utilizing Flow Using API component
• Deployments with stored API credentials in affected configurations

Discovery Timeline

• 2026-04-20 - CVE-2026-6597 published to NVD
• 2026-04-22 - Last updated in NVD database

Technical Details for CVE-2026-6597

Vulnerability Analysis

This vulnerability is classified under CWE-255 (Credentials Management Errors), indicating a fundamental flaw in how Langflow handles credential storage and retrieval. The affected functions remove_api_keys and has_api_terms in the core utilities module fail to properly protect stored credentials, leaving them accessible to unauthorized access.

The vulnerability can be exploited remotely by authenticated attackers with high-level privileges. While requiring elevated permissions limits the attack surface, successful exploitation could lead to credential theft and subsequent unauthorized access to integrated services and APIs.

A proof-of-concept exploit has been made publicly available, increasing the urgency for organizations using affected versions to apply mitigations. The vendor was contacted about this disclosure but did not respond.

Root Cause

The root cause lies in improper credential management within the remove_api_keys and has_api_terms functions in src/backend/base/langflow/api/utils/core.py. The implementation fails to adequately protect stored API credentials, violating secure credential storage best practices. This allows credentials to be stored or accessible in an unprotected manner, potentially exposing sensitive authentication data.

Attack Vector

The attack can be initiated remotely over the network by an authenticated attacker with high privileges. The attacker exploits the credential management flaw in the Flow Using API component to access unprotected credential storage. While network-based, the requirement for high privileges reduces the likelihood of opportunistic attacks, though it remains a significant risk for insider threats or attackers who have already compromised privileged accounts.

Technical details regarding the exploitation methodology can be found in the GitHub Gist PoC published by the security researcher. The vulnerability specifically targets the API utility functions responsible for handling credential operations within Langflow workflows.

Detection Methods for CVE-2026-6597

Indicators of Compromise

• Unexpected access attempts to credential storage locations within Langflow deployments
• Anomalous API requests targeting the Flow Using API component by privileged users
• Unauthorized retrieval or enumeration of stored API keys in application logs
• Evidence of credential extraction from core.py utility functions

Detection Strategies

• Monitor access logs for the src/backend/base/langflow/api/utils/core.py module for unusual activity
• Implement alerting for bulk credential access operations or unusual patterns in API key management
• Review audit logs for privileged user actions related to credential storage and retrieval
• Deploy file integrity monitoring on Langflow core configuration and utility files

Monitoring Recommendations

• Enable verbose logging for the Flow Using API component to capture credential-related operations
• Implement user behavior analytics for privileged accounts interacting with Langflow
• Configure alerts for access to credential storage mechanisms outside normal operational patterns
• Regularly audit stored credentials and API keys for unauthorized access or modifications

How to Mitigate CVE-2026-6597

Immediate Actions Required

• Upgrade Langflow to a patched version when available from langflow-ai
• Review and audit all stored API credentials within affected Langflow deployments
• Rotate any API keys that may have been exposed through vulnerable installations
• Restrict network access to Langflow instances to trusted sources only
• Implement additional access controls for privileged user accounts

Patch Information

At the time of publication, the vendor (langflow-ai) was contacted about this disclosure but did not respond. Organizations should monitor the official Langflow repository and security advisories for patch releases. Additional vulnerability details are available at VulDB Vulnerability #358232.

Workarounds

• Implement network segmentation to limit access to Langflow deployments from untrusted networks
• Apply principle of least privilege by restricting high-privilege access to essential personnel only
• Encrypt sensitive credentials at rest using external secrets management solutions
• Monitor and log all access to credential storage and API key management functionality

# Configuration example: Restrict Langflow network access
# Add to firewall rules or network security group

# Limit access to Langflow API to trusted internal networks only
iptables -A INPUT -p tcp --dport 7860 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 7860 -j DROP

# Consider using a reverse proxy with authentication
# nginx configuration snippet for additional access control
# location /api/ {
#     auth_basic "Restricted Access";
#     auth_basic_user_file /etc/nginx/.htpasswd;
#     proxy_pass http://localhost:7860;
# }