CVE-2026-19302: Langflow Information Disclosure Vulnerability

CVE-2026-19302 Overview

CVE-2026-19302 affects IBM Langflow OSS versions 1.0.0 through 1.11.2. The vulnerability allows a remote authenticated attacker to obtain sensitive information through improper validation of symbolic links [CWE-22]. Langflow is an open-source framework used to build agentic and retrieval-augmented generation (RAG) applications with a visual workflow interface.

The flaw stems from insufficient checks on symbolic links during file operations. An authenticated attacker can craft symlinks that resolve to files outside intended directories. This enables read access to sensitive host files that the Langflow process can access.

Critical Impact

Authenticated attackers can read arbitrary files accessible to the Langflow service, potentially exposing credentials, model configurations, and application secrets.

Affected Products

• Langflow OSS versions 1.0.0 through 1.11.2
• Deployments on Apple macOS
• Deployments on Linux and Microsoft Windows

Discovery Timeline

• 2026-09-04 - CVE-2026-19302 published to NVD
• 2026-09-08 - Last updated in NVD database

Technical Details for CVE-2026-19302

Vulnerability Analysis

The vulnerability is a path traversal issue rooted in symbolic link handling [CWE-22]. Langflow processes file paths without confirming that resolved targets remain within permitted directories. When a user references a symlink, the application follows it to its target without canonical path validation.

An authenticated user can create or upload a symbolic link pointing to sensitive locations on the host filesystem. When Langflow reads the referenced path, it returns the contents of the linked target. The scope is limited to confidentiality; the flaw does not permit modification or destruction of data.

Exploitation requires valid authentication to the Langflow instance, which reduces exposure in properly segmented deployments. However, Langflow environments used for collaborative AI workflow development often have multiple low-privilege accounts, expanding the risk surface.

Root Cause

The root cause is missing symbolic link validation before file read operations. The application does not resolve paths to their canonical form or verify that the resolved location falls within an allowed base directory. This omission enables directory traversal via symlink indirection rather than direct ../ sequences.

Attack Vector

The attack is delivered over the network against an authenticated Langflow session. The attacker plants a symlink through Langflow's file upload or component configuration interfaces. Subsequent read operations by the platform follow the symlink and return sensitive file contents to the attacker. Typical targets include /etc/passwd, environment files containing API keys, model provider credentials, and Langflow configuration files.

Refer to the IBM Support Page for vendor technical details.

Detection Methods for CVE-2026-19302

Indicators of Compromise

• Symbolic link files appearing in Langflow upload directories or user workspaces that point outside the application's data directory.
• File read events by the Langflow process targeting system paths such as /etc/, ~/.aws/, ~/.ssh/, or environment configuration files.
• Unusual authenticated API activity involving file component operations from a single account within a short interval.

Detection Strategies

• Audit Langflow container or host filesystems for symlinks whose targets resolve outside the application's working directory.
• Correlate authenticated Langflow user sessions with file access telemetry from the underlying host to identify out-of-scope reads.
• Monitor Langflow application logs for repeated file component executions referencing user-supplied paths.

Monitoring Recommendations

• Enable filesystem auditing on Langflow hosts using auditd on Linux or equivalent tooling on Windows and macOS.
• Forward Langflow application logs and host process telemetry to a centralized analytics platform for correlation.
• Alert on process reads of high-value files such as SSH keys, cloud provider credentials, and .env files performed by the Langflow service account.

How to Mitigate CVE-2026-19302

Immediate Actions Required

• Upgrade Langflow OSS to a version later than 1.11.2 as identified by IBM's advisory.
• Restrict Langflow authentication to trusted users and enforce strong credential policies.
• Run Langflow under a dedicated low-privilege service account with filesystem access confined to its data directory.

Patch Information

IBM has published remediation guidance on the IBM Support Page. Administrators should review the advisory and apply the fixed release for Langflow OSS. Verify the installed version with pip show langflow after upgrading.

Workarounds

• Deploy Langflow inside a container with a read-only root filesystem and bind-mount only required directories.
• Apply mandatory access controls such as SELinux or AppArmor profiles that deny reads outside the Langflow data path.
• Disable or restrict file upload and file component features for non-administrative users until the patch is applied.

# Configuration example: restrict Langflow container filesystem access
docker run -d \
  --name langflow \
  --read-only \
  --tmpfs /tmp \
  -v langflow_data:/app/data:rw \
  --cap-drop=ALL \
  --security-opt=no-new-privileges \
  -u 1001:1001 \
  langflowai/langflow:latest