CVE-2026-0770: Langflow exec_globals RCE Vulnerability

CVE-2026-0770 Overview

CVE-2026-0770 is a critical remote code execution vulnerability affecting Langflow, a popular open-source framework for building language model applications. This vulnerability allows remote attackers to execute arbitrary code on affected installations without requiring authentication, making it particularly dangerous for exposed deployments.

The vulnerability exists within the handling of the exec_globals parameter provided to the validate endpoint. The flaw results from the inclusion of a resource from an untrusted control sphere (CWE-829), allowing attackers to inject and execute malicious code. An attacker can leverage this vulnerability to execute code in the context of root, resulting in complete system compromise.

Critical Impact

Unauthenticated remote code execution allowing attackers to gain root-level access to affected Langflow installations

Affected Products

• Langflow (specific versions not disclosed in advisory)

Discovery Timeline

• 2026-01-23 - CVE-2026-0770 published to NVD
• 2026-01-26 - Last updated in NVD database

Technical Details for CVE-2026-0770

Vulnerability Analysis

This vulnerability is classified as CWE-829: Inclusion of Functionality from Untrusted Control Sphere. The flaw resides in Langflow's validate endpoint, which improperly handles the exec_globals parameter. This endpoint accepts user-supplied input that influences the execution context of code validation routines, allowing attackers to inject arbitrary functionality into the execution environment.

The vulnerability is particularly severe because it requires no authentication to exploit. Any attacker with network access to a Langflow instance can send specially crafted requests to the validate endpoint, manipulating the exec_globals parameter to achieve code execution with root privileges.

Root Cause

The root cause is improper input validation and insufficient isolation of the code execution environment within Langflow's validation functionality. The exec_globals parameter allows external control over global variables and functions available during code execution, effectively creating an untrusted code inclusion vulnerability. The application fails to properly sanitize or restrict what resources can be included through this parameter.

Attack Vector

The attack is network-based and can be performed remotely without any user interaction or authentication. An attacker sends a malicious HTTP request to the /validate endpoint with a crafted exec_globals parameter containing references to attacker-controlled resources or code. When the validation routine processes this parameter, it includes the malicious functionality, resulting in arbitrary code execution.

The vulnerability was initially tracked as ZDI-CAN-27325 by the Zero Day Initiative. For complete technical details and the security advisory, refer to the Zero Day Initiative Advisory ZDI-26-036.

Detection Methods for CVE-2026-0770

Indicators of Compromise

• Unusual HTTP POST requests to /api/v1/validate or similar validate endpoints containing exec_globals parameters
• Unexpected process spawning from Langflow worker processes, particularly with root privileges
• Network connections originating from Langflow services to external or suspicious hosts
• Log entries showing validation requests with abnormally large or encoded payloads

Detection Strategies

• Monitor HTTP traffic to Langflow instances for requests containing the exec_globals parameter with suspicious values
• Implement web application firewall (WAF) rules to detect and block malicious payloads targeting the validate endpoint
• Deploy endpoint detection and response (EDR) solutions to identify anomalous process behavior from Langflow services
• Enable verbose logging on Langflow instances and forward logs to a SIEM for correlation analysis

Monitoring Recommendations

• Configure alerting for any outbound network connections from Langflow containers or processes
• Monitor system calls and file system activity from Langflow processes for signs of post-exploitation activity
• Implement network segmentation monitoring to detect lateral movement attempts following potential compromise
• Review authentication logs for any unauthorized access attempts to Langflow management interfaces

How to Mitigate CVE-2026-0770

Immediate Actions Required

• Restrict network access to Langflow instances using firewall rules, limiting exposure to trusted networks only
• Implement authentication in front of Langflow if not already configured, using a reverse proxy with authentication
• Review Langflow access logs for any suspicious validation requests that may indicate exploitation attempts
• Consider temporarily disabling the validate endpoint if not required for operations

Patch Information

At the time of publication, specific patch information has not been disclosed in the CVE data. Organizations should monitor the Zero Day Initiative Advisory ZDI-26-036 and official Langflow release channels for security updates addressing this vulnerability. Apply patches immediately when available.

Workarounds

• Deploy a web application firewall (WAF) with rules to block requests containing potentially malicious exec_globals parameters
• Place Langflow instances behind a VPN or authentication gateway to prevent unauthenticated access
• Run Langflow with reduced privileges using containerization with appropriate security constraints
• Implement network segmentation to isolate Langflow instances from critical infrastructure

# Example: Block external access to Langflow using iptables
# Allow only internal network access to Langflow port (default 7860)
iptables -A INPUT -p tcp --dport 7860 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 7860 -j DROP