Description

IBM Langflow OSS 1.0.0 through 1.10.2 could allow a remote attacker to traverse directories on the system. An attacker could send a specially crafted URL request containing "dot dot " sequences ( /.. /) to view arbitrary files on the system.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.4",
  "pubDate": "2026-09-04T17:16:55.063Z",
  "pubdate": "2026-09-04T17:16:55.063Z",
  "executiveSummary": "IBM Langflow OSS versions 1.0.0 through 1.10.2 are susceptible to a Path Traversal vulnerability, classified as an Improper Limitation of a Pathname to a Restricted Directory.\nThis vulnerability allows unauthenticated remote attackers to bypass application-level access controls and retrieve arbitrary files from the underlying host filesystem.\nThe flaw stems from insufficient sanitization of user-supplied input in URL requests, specifically concerning path components.\nSuccessful exploitation grants an attacker the ability to access sensitive system configuration files, credentials, or application source code, depending on the permissions of the process running the Langflow service.\nThis presents a high risk to confidentiality, potentially leading to full system compromise or information disclosure if sensitive environment variables or configuration files are retrieved.\nThe vulnerability requires no prior authentication and can be executed via specially crafted HTTP requests targeting the affected endpoints.",
  "technicalDetails": "The vulnerability is rooted in the failure of the Langflow application to adequately validate and sanitize file path parameters provided within incoming URL requests. The application accepts path sequences containing 'dot dot' (../) segments, which are interpreted by the underlying filesystem API as directory traversal instructions.\nIn a secure implementation, the application should employ strict allow-listing or canonicalization checks to ensure that file access requests are confined to a designated web root or static asset directory. The affected versions of IBM Langflow OSS lack these boundary checks, allowing a request to escape the intended directory structure.\nAn attacker exploits this vulnerability by manipulating the path component of a URL request. By injecting sequence patterns such as '/../', the attacker traverses the server's directory tree. For instance, a request formatted as 'GET /path/to/resource/../../etc/passwd' instructs the web server to move up the directory hierarchy from the application's base path and target system-level files outside the scope of the web application.\nThe attack flow proceeds as follows: First, the attacker identifies an endpoint in the Langflow service that interacts with the local filesystem. Second, the attacker crafts a malicious URI containing multiple directory traversal sequences. Third, the application's input handling routine processes the URI without resolving the path to a canonical form or verifying that the target resides within the authorized directory. Fourth, the application proceeds to open and read the file specified by the traversed path, subsequently returning the contents to the attacker via the HTTP response body.\nThe impact of this vulnerability is significant, as it exposes the host's filesystem to unauthorized read operations. Attackers may target sensitive configuration files (e.g., .env files containing API keys, database credentials, or secret keys), system files (/etc/passwd, /etc/shadow), or proprietary application source code. The severity of the post-exploitation impact is dictated by the effective privileges of the user account under which the Langflow process is executing. If the service is running with elevated or root privileges, the risk of total system compromise is substantially increased."
}