CVE-2026-28288Public exploitNetwork attack vector

Email address enumeration via divergent login responses

Published Feb 27, 2026 · Updated Feb 27, 2026

Observable response discrepancy in Dify before 1.9.0 allows remote attackers to enumerate registered email addresses through the login API. POST /console/api/login returns a generic 401 response for an existing email with an incorrect password but a 400 account-not-found response for an unknown email. Unauthenticated network access is sufficient; brute-force protection limits repeated probes, and the direct consequence is disclosure of account existence.

CVSS severity5.3
Medium
EPSS probability0.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Observable response discrepancy in Dify before 1.9.0 allows remote attackers to enumerate registered email addresses through the login API. POST /console/api/login returns a generic 401 response for an existing email with an incorrect password but a 400 account-not-found response for an unknown email. Unauthenticated network access is sufficient; brute-force protection limits repeated probes, and the direct consequence is disclosure of account existence.

The record

CVE
CVE-2026-28288
Published
Feb 27, 2026
Updated
Feb 27, 2026
Vendor
LangGenius
Product
Dify
Classifications
CWE-204, T1589.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.9.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

LangGenius · Difyversion=< 1.9.0

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.5GitHub, Inc.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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-204Observable Response Discrepancy
T1589.003Gather Victim Identity Information: Employee Names

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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