CVE-2026-5027: Langflow | defend.network

What is CVE-2026-5027?

The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences ('../').

CVSS8.8 NVD 3.1

SeverityHIGH

Exploitation In the wild

EPSS36% · P98

Triage statusActive Exploit

ActionPatch within 48 hours

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CWECWE-22

NVD published2026-03-27

NVD last modified2026-08-18

Timeline

2026-03-27Published to the U.S. National Vulnerability Database (NVD)
2026-06-11First covered in a defend.network daily briefing
2026-08-18NVD record last updated

Affected product

Langflow

Remediation Steps

Apply the vendor security update for Langflow as a priority.
Restrict network exposure of the affected service to trusted sources until patched.
Review logs and detections for indicators of exploitation.
Confirm fixed versions against the official vendor advisory before deploying.

References

Referenced in our briefings & reports

Vulnerability Priority Report – Week 2 of June 2026 (June 8 – 14)
Langflow RCE exploited, JDY botnet expands U.S. military targeting, npm security hardened (2026-06-11)

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🤖 This CVE page is generated by defend.network from NVD, CISA KEV, EPSS, and our verified daily briefings. Severity and exploitation data come from official sources; always verify remediation steps against the official vendor advisory before acting in production.