Quick answers
- Is CVE-2026-76893 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-76893 being exploited in the wild.
- How severe is CVE-2026-76893?
- Medium severity, with a CVSS score of 4, published 4 November 2026.
- Which products and versions are affected?
- @tsparticles/mcp-server (npm) < 4.3.2, SEMVER:introduced=0,fixed=4.3.2; tsParticles @Tsparticles/Mcp-Server prior to 4.3.2.
- Is there a fix for CVE-2026-76893?
- Yes. @tsparticles/mcp-server (npm): upgrade to 4.3.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-76893 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-76893?
- Check whether you run @tsparticles/mcp-server (npm) or tsParticles @Tsparticles/Mcp-Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- @tsparticles/mcp-server (npm): upgrade to 4.3.2 or later
npm install @tsparticles/mcp-server@4.3.2
Technical details
The HTTP mode of @tsparticles/mcp-server uses a single stateful StreamableHTTPServerTransport for all clients without session isolation. An unauthenticated client sending the first initialize request without an mcp-session-id header claims the shared transport state, causing the server to return "Server already initialized" to all subsequent clients. This is a session management flaw that allows unauthenticated denial of service via network access to the HTTP endpoint; the fix in 4.3.2 implements per-session transport isolation and proper authentication.
Affected products
- tsParticles @tsparticles/mcp-server prior to 4.3.2
Identifiers
- CVE-2026-76893
- GHSA-h7c4-q426-7jh9
Timeline
- 2026-11-04: disclosed
- 2026-07-10: patched: Version 4.3.2 released with per-session HTTP transport and authentication controls