CVE-2026-79294: Moonshot AI Kimi XSS Vulnerability

CVE-2026-79294 Overview

CVE-2026-79294 is a Cross-Site Scripting (XSS) vulnerability in Moonshot AI Kimi, present in the version dated 2026-07-18. The flaw exists in the HTML artifact Preview rendering and the public Share view component. A remote attacker can craft an HTML artifact containing malicious script content that executes in the browser of any user who previews or opens the shared URL. Exploitation requires user interaction, such as clicking a shared Kimi link, but no authentication. The issue is classified under CWE-79: Improper Neutralization of Input During Web Page Generation.

Critical Impact
Attackers can execute arbitrary JavaScript in the context of the Kimi Share domain, enabling session token theft, phishing, and unauthorized actions against victim accounts.

Affected Products

Moonshot AI Kimi (version as of 2026-07-18)
Kimi HTML artifact Preview rendering component
Kimi public Share view component (Kimi Share)

Discovery Timeline

2026-09-18 - CVE-2026-79294 published to the National Vulnerability Database
2026-09-22 - Last updated in NVD database

Technical Details for CVE-2026-79294

Vulnerability Analysis

Moonshot AI Kimi allows users to generate and share HTML artifacts produced by the assistant. The Preview rendering path and the public Share view render user-supplied HTML without sufficient neutralization of active content. An attacker generates an artifact that embeds script tags, event handlers, or similar constructs, then shares the resulting URL. When a victim opens the link, the browser executes the attacker-controlled script in the origin serving the Share page. Because the vulnerability crosses a trust boundary between the attacker's content and the Kimi Share origin, it carries a scope change under CVSS.

Root Cause

The root cause is missing or incomplete output encoding and sanitization on HTML content stored in Kimi artifacts. The application treats generated artifact HTML as trusted markup and renders it directly in the Preview and Share view. Standard mitigations for [CWE-79], such as strict HTML sanitization allowlists or sandboxed iframes with restrictive Content Security Policy, are not applied to the affected code paths.

Attack Vector

The attack is network-based and requires user interaction. An attacker crafts a malicious HTML artifact in Kimi, publishes it through the Share feature, and distributes the resulting kimi.com/share/ URL through social engineering, phishing, or public posting. Any user who opens the link triggers script execution in the Share origin, exposing cookies, tokens, and any data reachable from that origin. Additional technical details and proof-of-concept material are available in the public PoC repository.

The vulnerability manifests when Kimi renders artifact HTML into the Preview and Share view without neutralizing embedded script content. See the referenced PoC for a working demonstration.

Detection Methods for CVE-2026-79294

Indicators of Compromise

Outbound requests from user browsers to unfamiliar domains immediately after a visit to kimi.com/share/.
Kimi Share URLs distributed through email, chat, or social channels from untrusted senders.
Unexpected authentication events or session activity on Kimi accounts following interaction with shared artifacts.

Detection Strategies

Inspect proxy and DNS logs for referrers matching kimi.com/share/ followed by connections to attacker-controlled infrastructure.
Hunt for browser telemetry showing script execution inside Kimi Share pages that references non-Kimi domains or exfiltration endpoints.
Correlate email and messaging gateway logs for delivery of Kimi Share links from external senders to high-value users.

Monitoring Recommendations

Enable Content Security Policy violation reporting on managed browsers to surface unexpected inline script execution on kimi.com.
Alert on anomalous data volume egressing from browser sessions to newly registered domains after visits to Kimi Share URLs.
Track user-agent activity to Kimi Share endpoints and flag repeated visits to the same artifact ID from distinct users, which may indicate a widely distributed malicious link.

How to Mitigate CVE-2026-79294

Immediate Actions Required

Instruct users to avoid opening Kimi Share links received from untrusted sources until Moonshot AI confirms a fix.
Restrict browser access to kimi.com/share/ for high-risk user groups through web proxy policies where feasible.
Rotate Kimi session credentials for any user who interacted with suspicious shared artifacts.

Patch Information

No vendor advisory or patched version was listed in the NVD entry at the time of publication. Monitor the Kimi vendor site and Moonshot AI for a security update addressing the HTML artifact Preview and Share view rendering paths.

Workarounds

Disable or restrict use of the Kimi Share feature within your organization until the vendor issues a fix.
Open Kimi Share links only in isolated browser profiles or sandboxed browsing environments that limit access to organizational credentials.
Deploy browser extensions or enterprise policies that enforce strict Content Security Policy on kimi.com to block inline script execution.

bash

# Example web proxy rule to block Kimi Share URLs for sensitive user groups
# Squid ACL example
acl kimi_share url_regex ^https?://kimi\.com/share/
http_access deny kimi_share sensitive_users