Summary
Langflow: Unauthenticated Flow Execution via Webhook Authentication Bypass
Impact
This is a High-severity Authentication Bypass.
- Remote Code Execution (RCE): Flows often contain components that execute arbitrary Python code. An attacker can leverage this to gain full control over the server.
- Denial of Service (DoS): Attackers can exhaust system resources by triggering heavy flows concurrently.
- Data Integrity: Unauthorized execution of flows can lead to unintended modification of databases or external systems connected via the flow.
A critical operation is accessible without requiring any authentication. Typical impact: any user can invoke the privileged function.
CVE-2026-8505 has a CVSS score of 9.8 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.9.1); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Fixed in v1.9.1 by PR #12845, fix(security): default WEBHOOK_AUTH_ENABLE to True. The setting's default changed from False to True, so webhook endpoints now require API key authentication and ownership validation by default, unless an operator explicitly opts out via LANGFLOW_WEBHOOK_AUTH_ENABLE=false.
Frequently Asked Questions
- What is CVE-2026-8505? CVE-2026-8505 is a critical-severity missing authentication for critical function vulnerability in langflow (pip), affecting versions >= 1.7.0, <= 1.9.0. It is fixed in 1.9.1. A critical operation is accessible without requiring any authentication.
- How severe is CVE-2026-8505? CVE-2026-8505 has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of langflow are affected by CVE-2026-8505? langflow (pip) versions >= 1.7.0, <= 1.9.0 is affected.
- Is there a fix for CVE-2026-8505? Yes. CVE-2026-8505 is fixed in 1.9.1. Upgrade to this version or later.
- Is CVE-2026-8505 exploitable, and should I be worried? Whether CVE-2026-8505 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-8505 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-8505? Upgrade
langflowto 1.9.1 or later.