CVE-2026-17630: IBM Langflow OSS RCE Vulnerability

CVE-2026-17630 Overview

CVE-2026-17630 affects IBM Langflow OSS versions 1.0.0 through 1.10.3. The flaw stems from improper validation of configuration parameters, allowing a remote authenticated attacker to execute arbitrary code on the underlying host. The weakness is classified under [CWE-184: Incomplete List of Disallowed Inputs], indicating that Langflow's validation logic fails to reject dangerous configuration values. Successful exploitation compromises the confidentiality, integrity, and availability of the affected Langflow instance and any workloads it can reach.

Critical Impact
Authenticated remote attackers can achieve arbitrary code execution on IBM Langflow OSS servers, gaining full control over AI workflow orchestration environments.

Affected Products

IBM Langflow OSS 1.0.0 through 1.10.3
Deployments exposing the Langflow configuration interface to authenticated users
Downstream systems and models orchestrated by vulnerable Langflow instances

Discovery Timeline

2026-08-05 - CVE-2026-17630 published to the National Vulnerability Database
2026-08-06 - Last updated in NVD database

Technical Details for CVE-2026-17630

Vulnerability Analysis

IBM Langflow OSS is a visual framework for building applications on top of large language models. The affected versions accept configuration parameters without applying complete validation against dangerous values. An attacker with existing high-privilege access on the Langflow instance can submit crafted parameters that the application then processes in a way that leads to arbitrary code execution. The vulnerability is reachable over the network and requires no user interaction, so a single compromised operator account or leaked API token is sufficient to trigger the flaw. Because Langflow instances frequently hold credentials to model providers, vector stores, and internal data sources, code execution on the host translates directly into broader lateral movement risk.

Root Cause

The root cause is an incomplete deny-list in Langflow's configuration parameter validation, matching the pattern described in [CWE-184]. Instead of enforcing a strict allow-list, the code filters against a limited set of disallowed inputs. Attackers can supply values that fall outside the deny-list yet still resolve to executable behavior when the configuration is applied.

Attack Vector

Exploitation requires network access to the Langflow API or UI along with high-privilege credentials. The attacker submits a malicious configuration payload through a legitimate endpoint. Langflow accepts the payload, and the unsafe value is later evaluated during flow execution or component initialization, yielding code execution in the service account context. No victim interaction is needed. Refer to the IBM Support Page for vendor-specific technical detail.

No verified proof-of-concept code is publicly available.
See the IBM advisory linked above for parameter-level guidance.

Detection Methods for CVE-2026-17630

Indicators of Compromise

Unexpected child processes spawned by the Langflow service account, particularly shells, python subprocesses, or network utilities
Outbound network connections from the Langflow host to unfamiliar domains or IP addresses shortly after a configuration change
Modifications to Langflow flow definitions, component code, or environment variables performed by administrative accounts outside of change windows

Detection Strategies

Audit Langflow API access logs for POST and PATCH requests targeting configuration or component endpoints, correlating them with the authenticated user identity
Monitor the Langflow process tree for execution of interpreters or system binaries that are not part of normal workflow runs
Alert on writes to Langflow configuration files, custom component directories, and any on-disk cache used for user-supplied code

Monitoring Recommendations

Forward Langflow application logs and host telemetry to a centralized analytics platform for correlation across identity, endpoint, and network sources
Baseline expected outbound destinations from Langflow servers and alert on deviations, especially to model providers or storage endpoints not in scope
Track privileged Langflow account usage and enforce alerting on new admin sessions from unfamiliar source addresses

How to Mitigate CVE-2026-17630

Immediate Actions Required

Upgrade IBM Langflow OSS to a fixed release beyond 1.10.3 as directed by the IBM Support Page
Restrict network exposure of Langflow administrative endpoints to trusted management networks or VPN segments
Rotate any API tokens, model provider keys, and service credentials stored in the Langflow environment

Patch Information

IBM has published guidance for CVE-2026-17630 on its support portal. Administrators should consult the IBM Support Page for the specific fixed version and upgrade procedure applicable to their deployment.

Workarounds

Limit high-privilege Langflow accounts to a minimal set of operators and enforce multi-factor authentication on every administrative login
Deploy Langflow inside a hardened container or sandbox with restricted filesystem, network egress, and capability sets to contain any successful code execution
Review and remove unnecessary custom components or configuration overrides until the upgrade is applied

bash

# Example: restrict outbound egress from a Langflow container to approved endpoints only
iptables -A OUTPUT -o eth0 -d <approved-model-endpoint> -j ACCEPT
iptables -A OUTPUT -o eth0 -j DROP