CVE-2026-19301 in Langflow OSS
Summary
by MITRE • 09/04/2026
IBM Langflow OSS 1.0.0 through 1.11.2 could allow a remote authenticated attacker to obtain sensitive information due to server-side request forgery.
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Analysis
by VulDB Data Team • 09/04/2026
The vulnerability identified in IBM Langflow versions 1.0.0 through 1.11.2 represents a critical security flaw rooted in Server-Side Request Forgery, commonly abbreviated as SSRF. This class of vulnerabilities occurs when an application accepts a URL or domain name from user input and subsequently makes requests to that specified destination without sufficiently validating the target address. In the context of IBM Langflow, which is designed for building and managing large language model applications, this flaw allows a remote authenticated attacker to manipulate internal network resources by crafting malicious requests that appear legitimate to the application server. The presence of authentication requirements indicates that while the attack surface is restricted to users with valid credentials, it does not mitigate the risk posed by compromised accounts or insider threats who may exploit this mechanism for unauthorized data access.
From a technical perspective, SSRF vulnerabilities typically arise when developers fail to implement strict allowlists for outbound connections or do not properly sanitize input parameters that dictate where server-side requests are directed. An attacker can leverage this weakness to force the vulnerable application to send HTTP requests to internal services that are otherwise inaccessible from the external network. These internal endpoints often include metadata service interfaces, database administration panels, cloud provider instance metadata APIs, and other sensitive backend components. By directing these requests toward local loopback addresses or private IP ranges, an attacker can extract configuration details, authentication tokens, and other secrets stored within the infrastructure environment surrounding the Langflow deployment.
The operational impact of this vulnerability is significant, particularly in environments where IBM Langflow is integrated with internal data sources or connected to sensitive backend systems. Successful exploitation could lead to unauthorized access to confidential information residing on adjacent servers or cloud instances. For instance, attackers might retrieve AWS EC2 metadata tokens which can be used to escalate privileges within a cloud environment, or they may access database credentials stored in configuration files accessible via local network paths. This not only compromises the confidentiality of data processed by Langflow but also potentially serves as an initial foothold for further lateral movement within the organization's internal network architecture.
To mitigate this risk, organizations running affected versions must immediately upgrade to a patched release that addresses the SSRF logic flaws. In addition to software updates, defensive measures should include implementing strict egress filtering rules at the firewall or proxy level to restrict outbound connections from application servers to only known and necessary destinations. It is also advisable to deploy network segmentation strategies that isolate Langflow instances from critical internal services such as databases and metadata endpoints. Furthermore, input validation mechanisms should be strengthened to reject any URLs containing private IP ranges, loopback addresses, or non-standard ports unless explicitly required for business operations. Regular security audits and penetration testing focused on SSRF vectors are recommended to ensure ongoing resilience against similar attack patterns aligned with CWE-918 and MITRE ATT&CK technique T1557.