CVE-2026-18430

HumHub 1.18.4 - Stored XSS in comment-deletion notifications through unescaped administrator reason

Published Aug 19, 2026 CVSS 4.0 · 7.2 High EPSS < 1% KEV · Not listed
Description
HumHub 1.18.4 contains a stored cross-site scripting vulnerability in the comment-deletion notification flow. A Space administrator can delete another user's comment, choose to notify the original author, and place HTML/JavaScript in the deletion reason.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description HumHub 1.18.4 contains a stored cross-site scripting vulnerability in the comment-deletion notification flow. A Space administrator can delete another user's comment, choose to notify the original author, and place HTML/JavaScript in the deletion reason.
Title HumHub 1.18.4 - Stored XSS in comment-deletion notifications through unescaped administrator reason
First Time appeared Humhub
Humhub humhub
Weaknesses CWE-79
CPEs cpe:2.3:a:humhub:humhub:1.18.4:*:linux:*:*:*:*:*
cpe:2.3:a:humhub:humhub:1.18.4:*:macos:*:*:*:*:*
cpe:2.3:a:humhub:humhub:1.18.4:*:windows:*:*:*:*:*
Vendors & Products Humhub
Humhub humhub
References
Metrics cvssV4_0

{'score': 7.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Fluid Attacks
Published
Updated
Aug 19, 2026, 7:21 PM
Reserved
Jul 30, 2026, 7:14 PM
Status
Deferred
Published
Aug 19, 2026, 4:17 PM
Modified
Oct 27, 2026, 11:10 AM