CVE-2026-97655 in Langflow OSS
Summary
by MITRE • 10/07/2026
IBM Langflow OSS 1.0.0 through 1.12.2 could allow a remote attacker to execute arbitrary code due to an incomplete blocklist in the code security scanner.
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Analysis
by VulDB Data Team • 10/07/2026
The vulnerability identified in IBM Langflow versions 1.0.0 through 1.12.2 represents a critical supply chain and runtime integrity risk stemming from insufficient input validation within its integrated code security scanning mechanisms. As an open-source framework designed to facilitate the creation of large language model applications, Langflow relies on automated tools to analyze Python dependencies for known vulnerabilities. However, the implementation of these scanners contains an incomplete blocklist that fails to adequately restrict or sanitize certain inputs before they are processed by underlying system commands. This architectural flaw allows a remote attacker who can influence the input data fed into the application's scanning interface to bypass security controls and inject malicious payloads directly into the execution environment.
From a technical perspective, this vulnerability is classified as an OS Command Injection, which aligns with CWE-78 in the Common Weakness Enumeration taxonomy. The root cause lies in the improper neutralization of special elements used in operating system commands. When the application processes user-supplied data for security scanning purposes, it does not sufficiently validate or escape characters that have special meaning to the shell interpreter. Consequently, an attacker can construct a specially crafted input string containing command separators and additional malicious instructions. Because the scanner executes these inputs with elevated privileges often associated with development environments, the injected commands are executed by the operating system rather than being treated as literal text strings intended for analysis.
The operational impact of this vulnerability is severe, enabling arbitrary code execution on the host machine running Langflow. An attacker does not necessarily need to exploit a flaw in the LLM logic itself but can instead target the infrastructure layer through the application's own security features. By leveraging incomplete blocklists, an adversary can achieve full control over the underlying operating system, potentially leading to data exfiltration, lateral movement within the network, or complete compromise of the development environment. This undermines the trust model of using automated scanners for dependency management and exposes organizations to significant risk if they rely on Langflow without strict input sanitization protocols in place.
In terms of threat modeling, this scenario maps directly to MITRE ATT&CK technique T1059, specifically Command and Scripting Interpreter sub-techniques such as T1059.004 for Unix Shell or T1059.007 for Windows Command Shell depending on the deployment platform. The attack vector is remote, requiring network access to interact with the Langflow interface, but it does not require authentication if the service is exposed without proper access controls. This highlights a broader industry challenge where security tools themselves become vectors for compromise due to inadequate input handling practices during their development phase.
Mitigation strategies must focus on immediate remediation and long-term architectural improvements. The primary recommendation is to upgrade IBM Langflow to version 1.12.3 or later, where the incomplete blocklist issue has been addressed by developers through rigorous input validation and parameterization of system calls. For organizations unable to patch immediately, deploying a Web Application Firewall with rules specifically designed to detect command injection patterns can provide a layer of defense in depth. Additionally, running Langflow within isolated containers or virtual machines with restricted privileges limits the blast radius should an exploitation attempt succeed. It is also critical to enforce strict access controls on the application interface and audit logs for any unusual execution patterns originating from security scanning modules.