What is CVE-2026-28288?

CVE-2026-28288 is a medium-severity vulnerability in Dify, classified under Observable Response Discrepancy. CVSS score: 5.3/10. Published 2026-02-27.

How severe is CVE-2026-28288?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Dify

CVE-2026-28288

Dify is an open-source LLM app development platform. Prior to 1.9.0, responses from the Dify API to existing and non-existent accounts differ, allowing an attacker to enumerate email addresses registered with Dify. Version 1.9.0 fixes the issue.

Published 2026-02-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.007 (51.7th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 51.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.007 · change: +0.001

Affected products

Dify
Langgenius Dify — versions < 1.9.0

Weakness classification (CWE)

CWE-204 — Observable Response Discrepancy

References

github.com/langgenius/dify/security/advisories/GHSA-9qpf-wcv3-w3qx (Exploit, Vendor Advisory)
github.com/langgenius/dify/issues/24323 (Issue Tracking)

Frequently asked questions

What is CVE-2026-28288?: CVE-2026-28288 is a medium-severity vulnerability in Dify, classified under Observable Response Discrepancy. CVSS score: 5.3/10. Published 2026-02-27.
How severe is CVE-2026-28288?: Medium severity. CVSS v3 base score is 5.3 out of 10.