Missing Authentication for Critical Function in Langflow - #VU142382
Published: August 13, 2026
Vulnerability identifier: #VU142382
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-306
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code or cause a denial of service.
The vulnerability exists due to missing authentication for a critical function in the webhook authentication logic in AuthService.get_webhook_user when handling webhook requests with webhook authentication disabled. A remote attacker can send a specially crafted POST request to trigger execution of a flow to execute arbitrary code or cause a denial of service.
Exploitation requires knowledge of a valid flow UUID and affects deployments where the webhook authentication setting is disabled.
Affected software
Langflow
Remediation
Install security update from vendor's website.
Langflow - update to 1.9.1