Description

IBM Langflow OSS 1.0.0 through 1.11.1 could allow a remote attacker to read arbitrary files due to path traversal.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.5",
  "pubDate": "2026-08-28T22:16:47.107Z",
  "pubdate": "2026-08-28T22:16:47.107Z",
  "executiveSummary": "IBM Langflow OSS versions 1.0.0 through 1.11.1 are susceptible to a path traversal vulnerability. This security flaw allows an unauthenticated remote attacker to bypass intended directory restrictions and read arbitrary files residing on the host filesystem. By manipulating input parameters that influence file path resolution, an attacker can traverse outside the designated application directories to access sensitive system files, configuration files, or proprietary data. The impact of this vulnerability is significant, as it leads to unauthorized information disclosure, potentially exposing system credentials, environment variables, or other sensitive assets necessary for further escalation or system compromise. The vulnerability stems from improper validation of user-supplied input used in file system operations. Exposure is inherent in any environment where the Langflow instance is accessible over the network, as the vulnerability does not explicitly require prior authentication to exploit. Organizations should prioritize updating to a remediated version once available or implementing strict access controls as a temporary mitigation strategy to limit exposure to this threat.",
  "technicalDetails": "The vulnerability in IBM Langflow OSS, affecting versions 1.0.0 through 1.11.1, constitutes a classic path traversal vulnerability, also known as directory traversal. This flaw arises from insufficient sanitization or validation of user-supplied file path inputs prior to their utilization in file system API calls. In the context of the affected application, the vulnerable component fails to adequately normalize input strings or restrict access to paths containing directory traversal sequences, such as '../'.\nAn attacker can exploit this vulnerability by crafting a malicious HTTP request that includes specially crafted file path parameters. When the application processes this input, the traversal sequences enable the resolution of paths outside the intended application root directory. By traversing the directory structure, the attacker can specify absolute or relative paths to files on the host operating system that the application process has permissions to access.\nThe attack flow proceeds as follows: First, the attacker identifies a request parameter or endpoint within Langflow that interacts with the filesystem, such as one responsible for file retrieval, log viewing, or template loading. Second, the attacker injects traversal sequences (e.g., '../../../../etc/passwd') into the identified parameter. Third, the application's backend code, failing to properly validate or sanitize the path, concatenates this input with the application's base directory, resulting in an effective path pointing to an arbitrary file on the server. Finally, the application returns the contents of the requested sensitive file to the attacker in the HTTP response.\nThe vulnerability does not necessarily require authentication to be exploited, significantly increasing the attack surface if the Langflow instance is exposed to a public network or an untrusted internal segment. Furthermore, the privilege level of the attacker is effectively that of the web application user; if the application is running with excessive privileges, the potential for accessing sensitive system configuration, application secrets, or database credentials is high. The post-exploitation impact includes, but is not limited to, the exposure of sensitive configuration files, source code, and environment variables, which can be leveraged to facilitate lateral movement, credential theft, or complete system compromise depending on the information retrieved."
}