Cyber Resilience

CVE-2026-28288

MediumPublic PoC

Published: 27 February 2026

Published
27 February 2026
Modified
09 March 2026
KEV Added
Patch
CVSS Score v4 5.5 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0045 64.2th percentile
Risk Priority 11 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-28288 is a medium-severity Observable Response Discrepancy (CWE-204) vulnerability in Dify Dify. Its CVSS base score is 5.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Email Addresses (T1589.002); ranked in the top 35.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

This vulnerability is AI-related — categorised as LLM Application Platforms; in the Privacy and Disclosure risk domain.

EU & UK References

Vulnerability details

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.

CWE(s)

AI Security AnalysisAI

AI Category
LLM Application Platforms
Risk Domain
Privacy and Disclosure
OWASP Top 10 for LLMs 2025
None mapped
Classification Reason
Matched keywords: dify, llm

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1589.002 Email Addresses Reconnaissance
Adversaries may gather email addresses that can be used during targeting.
Why these techniques?

Observable response discrepancy (CWE-204) directly enables email address enumeration via API queries.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

Affected Assets

dify
dify
≤ 1.9.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-204

Fake or randomized responses remove distinguishable success/failure signals attackers rely on.

addresses: CWE-204

Eliminates distinguishable response discrepancies in error conditions that could be exploited for reconnaissance.

References