HumHub 1.18.4 Comment-Deletion Notification Flow cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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2.4$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in HumHub 1.18.4. This vulnerability affects unknown code of the component Comment-Deletion Notification Flow. The manipulation results in cross site scripting. This vulnerability was named CVE-2026-18430. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in HumHub 1.18.4. It has been classified as problematic. Affected is an unknown functionality of the component Comment-Deletion Notification Flow. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. CVE summarizes:

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.

The advisory is available at fluidattacks.com. This vulnerability is traded as CVE-2026-18430 since 07/30/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Additional levels of successful authentication are necessary for exploitation. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 2.4
VulDB Meta Temp Score: 2.4

VulDB Base Score: 2.4
VulDB Temp Score: 2.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/30/2026 CVE reserved
08/19/2026 +20 days Advisory disclosed
08/19/2026 +0 days VulDB entry created
08/19/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: fluidattacks.com
Status: Not defined

CVE: CVE-2026-18430 (🔒)
GCVE (CVE): GCVE-0-2026-18430
GCVE (VulDB): GCVE-100-393198

Entryinfo

Created: 08/19/2026 18:23
Changes: 08/19/2026 18:23 (63)
Complete: 🔍
Cache ID: 216::103

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