Langflow – Stored XSS via Malicious SVG Upload_CVE-2026-5026

7 / 10

HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Description

The '/api/v1/files/images/{flow_id}/{file_name}' endpoint serves SVG files with the 'image/svg+xml' content type without sanitizing their content.

Since SVG files can contain embedded JavaScript, an attacker can upload a malicious SVG that executes arbitrary JavaScript when viewed by other users, leading to stored cross-site scripting (XSS). This allows stealing authentication tokens stored in cookies, including JWT access and refresh tokens.

Basic Information

ID CVE-2026-5026

Source tenable

Published Mar 27, 2026 at 14:50

Modified Mar 27, 2026 at 15:35

Affected Product

Vendor langflow-ai

Product langflow

Affected Versions langflow-ai langflow 0

CWE Classification

CWE-79

References

www.tenable.com /security/research/tra-2026-25

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