CVE-2025-34291

What is affected

Vendor	Langflow
Product	Langflow
Weakness	CWE-346

The vulnerability

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.

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

US federal civilian agencies were required to act by 4 June 2026 under BOD 22-01. The deadline is a compliance date, not a measure of severity — it says nothing about how dangerous the flaw is to anyone else.

Where this comes from

Every field on this page is taken from the CISA Known Exploited Vulnerabilities catalog, last synced 12 Nov 2026, 21:26. Nothing here is our own assessment. For the technical scoring, see the NVD record below.

NVD record ↗ CVE.org record ↗