Description

IBM Langflow OSS 1.0.0 through 1.11.1 is vulnerable to server-side request forgery (SSRF). This may allow an authenticated attacker to send unauthorized requests from the system, potentially leading to network enumeration or facilitating other attacks.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "4.3",
  "pubDate": "2026-08-28T22:16:46.743Z",
  "pubdate": "2026-08-28T22:16:46.743Z",
  "executiveSummary": "IBM Langflow OSS versions 1.0.0 through 1.11.1 are susceptible to a Server-Side Request Forgery (SSRF) vulnerability. This security flaw allows an authenticated user to coerce the application server into issuing unauthorized HTTP or network requests to arbitrary destinations.\nBy manipulating input parameters that the application utilizes to perform outbound requests, an attacker can bypass intended network access controls. This vulnerability poses a significant risk to internal infrastructure security, as it facilitates the reconnaissance of internal network segments that are otherwise inaccessible from the public-facing perimeter.\nThe successful exploitation of this flaw enables an attacker to interact with internal services, potentially leading to unauthorized data exfiltration, service disruption, or the facilitation of further exploitation chains targeting backend systems. The requirement for prior authentication acts as a baseline constraint; however, in environments with multiple users or compromised accounts, this risk remains critical. Organizations are urged to review internal network security policies and ensure that the host environment for IBM Langflow is strictly segmented to minimize the potential blast radius of such outbound requests.",
  "technicalDetails": "The SSRF vulnerability in IBM Langflow OSS 1.0.0 through 1.11.1 originates from inadequate validation and sanitization of user-supplied input used to initialize outbound network connections. Within the application's core logic, specific functional modules process external URLs or endpoint configurations provided by the user. If the application logic fails to implement a strict allowlist of permitted hosts, ports, or protocols, it effectively acts as a proxy for malicious requests.\nThe exploitation flow typically begins with an authenticated attacker interacting with the application's interface or API endpoints designed for third-party integrations, data ingestion, or flow configuration. By injecting a crafted URL into these input fields—such as targeting internal IP addresses (e.g., 127.0.0.1 or non-routable private address spaces) or specific internal service ports—the attacker directs the server to initiate an outbound request on their behalf.\nTechnically, the vulnerability manifests when the backend server processes these requests without performing an egress filter check against the target destination. When the application executes the request, it includes any locally available credentials or headers, which may be implicitly trusted by internal services. Consequently, the attacker can leverage the server as a pivot point to perform network enumeration, mapping out internal services, scanning open ports, or querying cloud metadata services (e.g., 169.254.169.254) if the instance is deployed in a cloud environment.\nThe impact of this SSRF is significant because it subverts the trust boundary between the external-facing application and the internal protected network. Beyond mere enumeration, an attacker might interact with internal REST APIs, database management interfaces, or control planes that lack robust authentication, relying instead on network-level security. The absence of proper input validation ensures that the server's network stack can be abused to make requests using protocols supported by the underlying libraries (e.g., HTTP, HTTPS, or potentially others depending on the implementation), allowing the attacker to interact with diverse network-based assets. Post-exploitation impact ranges from information leakage of sensitive internal configurations to the lateral movement across the internal infrastructure."
}