CVE-2026-76893 (GCVE-0-2026-76893)
Vulnerability from cvelistv5 – Published: 2026-11-04 22:10 – Updated: 2026-11-05 20:20
VLAI
EPSS
VEX
Title
tsParticles: A single anonymous MCP session can monopolize HTTP mode and deny new clients
Summary
tsParticles is a TypeScript library for creating highly customizable particle animations. Prior to 4.3.2, the HTTP mode of @tsparticles/mcp-server reuses one stateful StreamableHTTPServerTransport for every client. An unauthenticated client that sends the first initialize request without an mcp-session-id claims the shared transport state, causing later independent clients to receive Server already initialized and preventing them from establishing sessions until the process restarts. The first client's session remains functional. This issue is fixed in version 4.3.2.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-05 20:20 UTC
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/tsparticles/tsparticles/securi… | x_refsource_CONFIRM |
| https://github.com/tsparticles/tsparticles/pull/5888 | x_refsource_MISC |
| https://github.com/tsparticles/tsparticles/commit… | x_refsource_MISC |
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| tsparticles | tsparticles |
Affected:
< 4.3.2
|
guessed | |
| @tsparticles | mcp-server |
Affected:
< 4.3.2
|
guessed |
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vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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