Vulnerability Analysis
HumHub Community Edition 1.18.4-pl1 - Reflected XSS in Space membership request button rendering
CVE-2026-18756
HumHub Community Edition 1.18.4 contains a reflected cross-site scripting vulnerability in the Space membership-request workflow. An attacker can place attacker-controlled button configuration in the options query-string parameter of space/membership/request-membership-form, lure an authenticated non-member into submitting the legitimate membership request form, and cause the server to return JavaScript containing attacker-controlled code.
Cross-Site Scripting (XSS)
No Active Exploit Signals
CVSS Base Score
7.2
HIGH
Exploitability:-
Impact Score:-
Temporal Score:-
EPSS:-
Threat Intelligence Signals
CISA KEV
No
KEV Date Added
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Ransomware Use
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KEV Due Date
—
VulnCheck In-the-Wild
No
Nuclei Template
No
EPSS Score
—
EPSS Percentile
—
GHSA ID
—
GitHub Severity
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SSVC Exploitation
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SSVC Automatable
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Vulnerability Class
Cross-Site Scripting (XSS)
Identity & Timeline
| Status | - |
| Assigning Authority | - |
| CVSS Version / Source | - |
| Reserved | - |
| Published | - |
| Patch Date (date_public) | - |
| Exploit DB Date | - |
| First GitHub PoC Date | - |
| Last Updated | - |
| Time to Patch (Days to fix) | - |
| Exploit Release Gap | - |
| PoC Release Gap | - |
| Exploit DB References | None identified |
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| No affected products specified. | ||
Social Buzz