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.

CVSS

No CVSS.

References

Link	Resource
https://fluidattacks.com/es/advisories/turizo
https://github.com/humhub/humhub
https://github.com/humhub/humhub/pull/8381

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 15:16

Updated : 2026-08-28 15:31

NVD link : CVE-2026-18756

Mitre link : CVE-2026-18756

CVE.ORG link : CVE-2026-18756

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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