What it is
Langflow contains an origin validation error vulnerability in which an overly permissive CORS configuration combined with a refresh token cookie configured as SameSite=None allows a malicious webpage to perform cross-origin requests that include credentials and successfully call the refresh endpoint. This could allow the attacker to execute arbitrary code and achieve full system compromise via obtained tokens that permit access to authenticated endpoints.
What to do
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vendor notices and references
- github.com/langflow-ai/langflow/releases/tag/v1.9.3
- github.com/langflow-ai/langflow/issues/11465#event-25774545848
- nvd.nist.gov/vuln/detail/CVE-2025-34291
Description and required action as published by CISA. Full record at NVD.
Other Langflow entries on the list
- Langflow Langflow Inclusion of Functionality from Untrusted Control Sphere Vulnerability CVE-2026-0770 · Jul 21, 2026
- Langflow Langflow Authorization Bypass Through User-Controlled Key Vulnerability CVE-2026-55255 · Jul 7, 2026
- Langflow Langflow Code Injection Vulnerability CVE-2026-33017 · Mar 25, 2026
- Langflow Langflow Missing Authentication Vulnerability CVE-2025-3248 · May 5, 2025