XSS in Langgenius Dify
CVE-2026-42138
Dify is an open-source LLM app development platform. Prior to version 1.13.1, using the method POST /api/files/upload, any unauthenticated user can upload an SVG file with XSS. The method POST /v1/files/upload, which requires authentication through the application API, is also vulnerable. This issue has been patched in version 1.13.1.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (24.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 24.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Langgenius Dify — versions < 1.13.1
Weakness classification (CWE)
References
- github.com/langgenius/dify/security/advisories/GHSA-cg94-8v83-7hjj (Exploit, Vendor Advisory)
- github.com/langgenius/dify/releases/tag/1.13.1 (Release Notes)
Frequently asked questions
- What is CVE-2026-42138?
- CVE-2026-42138 is a medium-severity vulnerability in Langgenius Dify, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-05-04.
- How severe is CVE-2026-42138?
- Medium severity. CVSS v3 base score is 6.1 out of 10.