CVE-2026-9196: IBM Langflow OSS RCE Vulnerability

CVE-2026-9196 Overview

CVE-2026-9196 affects IBM Langflow OSS versions 1.0.0 through 1.10.3. The vulnerability allows an authenticated attacker to execute unintended code during Agentic Assistant validation. Langflow improperly handles Large Language Model (LLM) generated components and executes model-generated Python code in the backend prior to user approval. Attackers can trigger outbound network access, file system interaction, or data exfiltration with the privileges of the Langflow backend process. The issue is tracked as [CWE-94] Improper Control of Generation of Code.

Critical Impact
Authenticated attackers can execute arbitrary Python code within the Langflow backend, enabling data exfiltration and lateral movement from the LLM validation path.

Affected Products

IBM Langflow OSS 1.0.0 through 1.10.3
Deployments using the Agentic Assistant validation feature
Backend processes handling LLM-generated components

Discovery Timeline

2026-08-05 - CVE-2026-9196 published to NVD
2026-08-06 - Last updated in NVD database

Technical Details for CVE-2026-9196

Vulnerability Analysis

CVE-2026-9196 stems from unsafe execution of LLM-generated Python code inside the Langflow backend. During Agentic Assistant validation, Langflow executes model-produced component code before a user reviews or approves the output. This design allows any authenticated user who can influence the LLM prompt or the generated component to reach a code execution path. The executed code runs with the privileges of the Langflow backend process, granting access to local files, environment variables, and network egress. IBM classifies the flaw under [CWE-94] Improper Control of Generation of Code.

Root Cause

The root cause is a missing trust boundary between LLM output and code execution. Langflow treats model-generated Python as validated input rather than untrusted content. No sandbox, allow-list, or approval gate separates generation from execution. Any side effect expressible in Python, including subprocess spawning and outbound HTTP requests, becomes reachable during validation.

Attack Vector

An authenticated attacker interacts with the Agentic Assistant to influence generated components. When Langflow validates the generated flow, the injected Python executes server-side. Attackers can steal API keys stored in environment variables, read model artifacts, or pivot to internal services reachable from the Langflow host. See the IBM Support Page for vendor technical details.

// No verified public proof-of-concept code is available.
// See the IBM advisory for vendor-supplied technical detail.

Detection Methods for CVE-2026-9196

Indicators of Compromise

Unexpected outbound network connections originating from the Langflow backend process to attacker-controlled hosts.
Unusual file system reads or writes performed by the Langflow service account, particularly against credential stores or .env files.
Agentic Assistant validation events immediately followed by subprocess creation or Python os, socket, or requests activity.

Detection Strategies

Monitor Langflow backend processes for anomalous child processes spawned during flow validation.
Inspect application logs for repeated Agentic Assistant validation requests from a single authenticated principal.
Alert on process telemetry showing Langflow executing code that touches sensitive paths or performs DNS lookups to new domains.

Monitoring Recommendations

Enable verbose audit logging for authenticated Langflow API sessions, including component generation and validation events.
Forward host and network telemetry from Langflow servers to a centralized analytics platform for correlation.
Baseline normal Agentic Assistant behavior and flag deviations in code content, execution duration, or egress patterns.

How to Mitigate CVE-2026-9196

Immediate Actions Required

Upgrade IBM Langflow OSS to a fixed release beyond 1.10.3 as directed by the IBM Support Page.
Restrict Langflow access to trusted, authenticated users and enforce least-privilege on the backend service account.
Block outbound network egress from Langflow hosts to any destination not required for operation.

Patch Information

IBM has published remediation guidance for CVE-2026-9196 on the IBM Support Page. Administrators should apply the vendor-supplied fixed version and validate that Agentic Assistant validation no longer executes unreviewed LLM-generated Python.

Workarounds

Disable the Agentic Assistant feature until the patched version is deployed.
Run Langflow inside an isolated container with read-only file systems and no access to production secrets.
Apply strict network egress policies that block outbound traffic from the Langflow backend to the internet.

bash

# Example: restrict Langflow container network egress and drop capabilities
docker run --rm \
  --network internal_only \
  --read-only \
  --cap-drop=ALL \
  --user 10001:10001 \
  -e LANGFLOW_AGENTIC_ASSISTANT_ENABLED=false \
  langflowai/langflow:patched