# CVE-2026-63655: tsParticles: Unbounded HTTP Request Body Buffering in @tsparticles/mcp-server Leads to Remote DoS

Status: published. Published: 2026-11-04. Updated: 2026-11-06.

tsParticles is a TypeScript library for creating highly customizable particle animations. Prior to 4.3.1, the HTTP mode of @tsparticles/mcp-server accepts unauthenticated POST /mcp requests in integrations/mcp-server/src/index.ts and accumulates every request-body chunk in a Buffer[] without a cumulative size limit before Buffer.concat and JSON.parse. A remote attacker can stream an arbitrarily large body to exhaust Node.js process memory and terminate the service, including in the official Docker configuration that exposes HTTP mode on 0.0.0.0:3000. Confidentiality and integrity are not affected. This issue is fixed in version 4.3.1.

## Remediation

- fix: @tsparticles/mcp-server (npm): GitHub reports patched versions 4.3.1. Check the advisory for the affected release branch. (source: GitHub GHSA-447x-qqwf-m7xq) — https://github.com/tsparticles/tsparticles/security/advisories/GHSA-447x-qqwf-m7xq

## Affected products and versions

- tsparticles / tsparticles: < 4.3.1 (affected). Source: CNA: GitHub_M
- @tsparticles / mcp-server: < 4.3.1 (affected). Source: CNA: GitHub_M
-  / @tsparticles/mcp-server (@tsparticles/mcp-server): <= 4.3.0 (affected, GitHub advisory range). Source: GitHub GHSA-447x-qqwf-m7xq

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: GitHub_M

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: security-advisories@github.com

- CISA KEV: No listing in collected sources

- EPSS: 0.43% as of 2026-11-05; percentile 37.52%

- SSVC: exploitation poc; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-400

## Exploit evidence

- exploit: https://github.com/tsparticles/tsparticles/security/advisories/GHSA-447x-qqwf-m7xq (ADP: CISA-ADP)

## References

- https://github.com/tsparticles/tsparticles/security/advisories/GHSA-447x-qqwf-m7xq (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/tsparticles/tsparticles/pull/5875 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/tsparticles/tsparticles/commit/25fb70e7f527a91568adaef576570289083f243b (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/tsparticles/tsparticles/commit/7b3a9488d4201fe9ddd5fec05f4a2ae65d3627ea (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/tsparticles/tsparticles/releases/tag/v4.3.1 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/tsparticles/tsparticles/security/advisories/GHSA-447x-qqwf-m7xq (ADP: CISA-ADP; exploit)

- https://github.com/tsparticles/tsparticles/commit/25fb70e7f527a91568adaef576570289083f243b (security-advisories@github.com)

- https://github.com/tsparticles/tsparticles/commit/7b3a9488d4201fe9ddd5fec05f4a2ae65d3627ea (security-advisories@github.com)

- https://github.com/tsparticles/tsparticles/pull/5875 (security-advisories@github.com)

- https://github.com/tsparticles/tsparticles/releases/tag/v4.3.1 (security-advisories@github.com)

- https://github.com/tsparticles/tsparticles/security/advisories/GHSA-447x-qqwf-m7xq (security-advisories@github.com)

- https://github.com/tsparticles/tsparticles/security/advisories/GHSA-447x-qqwf-m7xq (134c704f-9b21-4f2e-91b3-4a467353bcc0)

- https://github.com/tsparticles/tsparticles/security/advisories/GHSA-447x-qqwf-m7xq (GitHub Security Advisories; advisory)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2026-63655; retrieved 2026-11-05; source updated 2026-11-05

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-63655; retrieved 2026-11-07; source updated 2026-11-06

- GitHub Security Advisories: https://github.com/tsparticles/tsparticles/security/advisories/GHSA-447x-qqwf-m7xq; retrieved 2026-11-06; source updated 2026-07-17

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-63655; retrieved 2026-11-05; source updated Not reported

Revision: 5e2ba87ba2a095e0872df9636838ba5aa39ef264e21c3453294413a017c393d0

Canonical: https://y2.dev/cve/CVE-2026-63655

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