CVE-2026-79725 in Langflow OSS
Summary
by MITRE • 09/10/2026
IBM Langflow OSS 1.0.0 through 1.11.5 could allow a remote authenticated attacker to read arbitrary files due to improper access control.
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Analysis
by VulDB Data Team • 09/10/2026
The vulnerability identified in IBM Langflow versions 1.0.0 through 1.11.5 represents a critical security flaw rooted in insufficiently enforced access controls within the application's file handling mechanisms. As an open-source framework designed for building and deploying large language model applications, Langflow processes various user inputs to generate dynamic workflows. However, the underlying implementation fails to adequately sanitize or validate file paths provided by authenticated users before processing them. This oversight allows a remote attacker who has successfully obtained valid credentials to manipulate these input parameters, thereby bypassing intended security boundaries that restrict access to specific directories or files within the host system's filesystem.
From a technical perspective, this flaw is classified as an improper restriction of excessive functionality or resources, specifically manifesting as path traversal when interacting with file systems. The attacker can exploit this by supplying maliciously crafted input strings containing directory traversal sequences such as dot-dot-slash characters. Because the application does not strictly validate these paths against a whitelist of allowed directories or normalize them to prevent escape from the intended context, it proceeds to read the specified resource regardless of its actual location on the disk. This behavior aligns with Common Weakness Enumeration identifier CWE-22, which describes Improper Limitation of a Pathname to a Restricted Directory, commonly known as path traversal attacks. The vulnerability persists because the authentication layer verifies user identity but fails to enforce granular authorization policies that restrict what specific resources each authenticated session can access.
The operational impact of this vulnerability is severe for organizations relying on Langflow for sensitive data processing or internal tooling development. An attacker with low-privilege credentials could leverage this flaw to read arbitrary files from the server, potentially exposing configuration files containing database connection strings, API keys, secret tokens, and other sensitive authentication materials. In environments where Langflow is integrated with backend systems that store proprietary logic or customer data in accessible file locations, this exposure can lead to a complete compromise of confidentiality. Furthermore, if the application runs with elevated privileges or has access to critical system files, the attacker could potentially extract kernel configurations or user credentials stored on disk, significantly expanding the attack surface for subsequent lateral movement within the network infrastructure.
This vulnerability maps directly to several tactics and techniques defined in the MITRE ATT&CK framework. It falls under the Initial Access tactic via Valid Accounts, as it requires prior authentication. The exploitation technique corresponds to Data from Local System Retrieval, specifically utilizing File and Directory Discovery methods where the attacker enumerates and reads sensitive files without triggering standard intrusion detection alerts due to the use of legitimate application functions abused for malicious purposes. This makes detection challenging unless specific file access patterns are monitored closely by endpoint protection systems or web application firewalls configured with advanced behavioral analysis capabilities.
To mitigate this risk, organizations running affected versions must immediately upgrade IBM Langflow to version 1.12.0 or later where the path validation logic has been hardened. In addition to upgrading, administrators should implement strict input validation on all file-related endpoints, ensuring that only whitelisted directories are accessible and that any user-supplied paths are normalized and checked against a secure base directory before processing. Principle of least privilege should be applied by running the Langflow service under a dedicated non-root account with restricted filesystem permissions, limiting the potential damage even if an attacker successfully exploits this vulnerability. Regular security audits and static code analysis tools focused on detecting path traversal weaknesses can further help identify similar issues in custom integrations or extensions built upon the framework.