CVE-2026-107328 in Langflow OSS
Summary
by MITRE • 10/29/2026
IBM Langflow OSS 1.0.0 through 1.12.4 could allow a remote authenticated attacker to execute arbitrary code due to improper neutralization of code in eval/exec.
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Analysis
by VulDB Data Team • 10/29/2026
The vulnerability identified in IBM Langflow versions 1.0.0 through 1.12.4 represents a critical security flaw rooted in the improper handling of user-supplied input within dynamic code execution functions. Specifically, the application utilizes Python's built-in eval and exec functions to process data provided by authenticated users without adequate sanitization or validation mechanisms. This architectural decision creates a direct pathway for remote attackers who have valid credentials to inject malicious payloads that are subsequently interpreted as executable code by the underlying runtime environment. The core technical flaw lies in the failure to neutralize special elements within user input, allowing an attacker to bypass intended logic and execute arbitrary commands on the host system where Langflow is deployed. This type of vulnerability is formally classified under CWE-95, which addresses Improper Neutralization of Directives for Dynamically Evaluated Code, commonly known as injection vulnerabilities involving code execution contexts.
From a technical perspective, the eval function in Python evaluates a string as a Python expression, while exec executes arbitrary Python code contained within a string. When these functions are exposed to user input without rigorous filtering or sandboxing, they effectively grant the attacker control over the application's runtime behavior. An authenticated adversary can craft specific strings containing malicious Python statements that leverage standard library modules such as os or subprocess to interact with the operating system. This interaction can lead to file manipulation, data exfiltration, or further lateral movement within the network infrastructure hosting the Langflow instance. The severity of this issue is compounded by the fact that it requires authentication, which may provide a false sense of security; however, once an attacker obtains valid credentials through phishing, credential stuffing, or other means, the barrier to achieving remote code execution is effectively removed.
The operational impact of this vulnerability extends beyond simple service disruption. Successful exploitation allows for complete compromise of the underlying server environment, potentially leading to unauthorized access to sensitive data stored within Langflow's associated databases or file systems. Attackers can use the compromised instance as a pivot point to attack other internal services, exfiltrate proprietary model configurations, or deploy additional malware such as cryptominers or ransomware. In enterprise environments where Langflow is used for managing large language models and AI workflows, this compromise could disrupt critical business operations and lead significant reputational damage due to the exposure of intellectual property and customer data. The ability to execute arbitrary code means that the confidentiality, integrity, and availability of the entire system are at risk, aligning with high-severity ratings in standard vulnerability scoring systems like CVSS.
Mitigation strategies must focus on immediate remediation through software updates and long-term architectural improvements. IBM has released patched versions beyond 1.12.4 to address this specific flaw; therefore, administrators should prioritize upgrading the Langflow installation to the latest stable release as soon as possible. In cases where an upgrade is not immediately feasible, temporary mitigations include restricting network access to the Langflow interface to trusted IP ranges and enforcing strict multi-factor authentication to reduce the likelihood of credential compromise. Furthermore, developers reviewing custom integrations or extensions should audit any usage of eval or exec functions, replacing them with safer alternatives such as JSON parsing for data structures or dedicated libraries designed for safe expression evaluation that do not allow arbitrary code execution. Implementing a Web Application Firewall can also provide an additional layer of defense by filtering out known malicious patterns in HTTP requests before they reach the application logic.
This vulnerability maps directly to several techniques within the MITRE ATT&CK framework, particularly T1059 Command and Scripting Interpreter, which covers the use of scripting languages like Python for execution purposes. It also relates to T1203 Exploitation for Client Execution if the attack vector involves client-side components, though in this server-centric context, it primarily reflects direct exploitation of a service component. Understanding these mappings helps security teams align their detection rules and incident response procedures with established industry standards. By recognizing that improper neutralization leads directly to code execution, organizations can better prioritize patching efforts and enhance monitoring for suspicious activities indicative of post-exploitation behaviors such as process creation or file system modifications originating from the Langflow service account.