NextChat HTMLPreview HTML injection

CVSS Meta Temp Score
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CTI Interest Score
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3.5$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in NextChat. Affected is an unknown function of the component HTMLPreview. Such manipulation leads to HTML injection. This vulnerability is listed as CVE-2025-50733. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in NextChat (version unknown) and classified as problematic. Affected by this issue is an unknown function of the component HTMLPreview. The manipulation with an unknown input leads to a html injection vulnerability. Using CWE to declare the problem leads to 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. Impacted is integrity. CVE summarizes:

NextChat contains a cross-site scripting (XSS) vulnerability in the HTMLPreview component of artifacts.tsx that allows attackers to execute arbitrary JavaScript code when HTML content is rendered in the AI chat interface. The vulnerability occurs because user-influenced HTML from AI responses is rendered in an iframe with 'allow-scripts' sandbox permission without proper sanitization. This can be exploited through specifically crafted prompts that cause the AI to generate malicious HTML/JavaScript code. When a user views the HTML preview, the injected JavaScript executes in the user's browser context, potentially allowing attackers to exfiltrate sensitive information (including API keys stored in localStorage), perform actions on behalf of the user, and steal session data.

The advisory is shared for download at hackmd.io. This vulnerability is handled as CVE-2025-50733 since 06/16/2025. The exploitation is known to be easy. The attack may be launched remotely. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1059.007.

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

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.5
VulDB Meta Temp Score: 3.5

VulDB Base Score: 3.5
VulDB Temp Score: 3.5
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: HTML injection
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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

06/16/2025 CVE reserved
08/22/2025 +67 days VulDB entry created
08/23/2025 +0 days Advisory disclosed
08/23/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: hackmd.io
Status: Not defined

CVE: CVE-2025-50733 (🔒)
GCVE (CVE): GCVE-0-2025-50733
GCVE (VulDB): GCVE-100-321188

Entryinfo

Created: 08/23/2025 00:05
Changes: 08/23/2025 00:05 (52)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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