CVE-2026-28288: langgenius dify · Observable Response Discrepancy
Affects langgenius difySource CVE Database V5
Public exploit available · CVSS 5.5 Medium : upgrade to 1.9.0 as a priority.
Data as of 29 Oct 2026, 19:04 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 52% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.9.0
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:PExploitation evidence
Disclosed: evidence found.
CVE published 27 Feb 2026
Detectable: evidence found.
nuclei template: Dify User Enumeration via Observable Response Discrepancy
Weaponized: evidence found.
CVSS exploit maturity: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade dify and langgenius/dify to 1.9.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| langgeniusdify | Affected
| Fixed in
|
GitHublanggenius/difypkg:github/langgenius/difyOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
To mitigate CVE-2026-28288, organizations should immediately upgrade all Dify instances to version 1.9.0 or later, where the vulnerability is patched. If upgrading is not immediately feasible, implement network-level controls such as rate limiting and IP blacklisting to reduce the risk of automated enumeration attempts. Additionally, monitor API access logs for unusual patterns indicative of enumeration, such as high volumes of email verification requests from single IP addresses. Employ application-layer protections like web application firewalls (WAFs) configured to detect and block enumeration behaviors. Educate users about phishing risks and encourage strong, unique passwords combined with multi-factor authentication (MFA) to mitigate risks from potential credential stuffing attacks. Finally, review and minimize the amount of information returned in API error messages or responses to avoid leaking account existence details.
Description
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.