SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-50733

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.

MEDIUM 6.1EPSS 0.20%

Does this matter?

Lower severity and a low EPSS score (0.20%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 3.1
6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS
0.20% probability · 10th percentile
CISA KEV
Not listed
Weakness
CWE-79
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.