Is CVE-2026-102600 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-102600 being exploited in the wild.

How severe is CVE-2026-102600?

High severity, with a CVSS score of 7.5, published 29 September 2026.

Which products and versions are affected?

@socket.io/cluster-engine (npm) < 0.1.1, SEMVER:introduced=0,fixed=0.1.1; Socket.IO Cluster-Engine prior to 0.1.1.

Is there a fix for CVE-2026-102600?

Yes. @socket.io/cluster-engine (npm): upgrade to 0.1.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-102600 attacked?

It is attacked over the network.

Am I affected by CVE-2026-102600?

Check whether you run @socket.io/cluster-engine (npm) or Socket.IO Cluster-Engine 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.

CVE-2026-102600: Socket.IO cluster-engine prototype pollution denial of service

Q: Is there a fix for CVE-2026-102600?

Yes. @socket.io/cluster-engine (npm): upgrade to 0.1.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-102600 attacked?

It is attacked over the network.

Q: Am I affected by CVE-2026-102600?

Check whether you run @socket.io/cluster-engine (npm) or Socket.IO Cluster-Engine 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.

CVE-2026-102600 · Severity: high · CVSS 7.5 · Published 2026-09-29

Socket.IO cluster-engine is a library that enables real-time communication in distributed Node.js applications. The library is vulnerable to a prototype pollution attack where specially crafted session IDs can crash the Node.js process, causing service outages. Applications not using the cluster-engine component are unaffected, and the issue is fixed in version 0.1.1.

Vendors: npm, Socket.IO.

Quick answers

Is CVE-2026-102600 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-102600 being exploited in the wild.
How severe is CVE-2026-102600?: High severity, with a CVSS score of 7.5, published 29 September 2026.
Which products and versions are affected?: @socket.io/cluster-engine (npm) < 0.1.1, SEMVER:introduced=0,fixed=0.1.1; Socket.IO Cluster-Engine prior to 0.1.1.
Is there a fix for CVE-2026-102600?: Yes. @socket.io/cluster-engine (npm): upgrade to 0.1.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-102600 attacked?: It is attacked over the network.
Am I affected by CVE-2026-102600?: Check whether you run @socket.io/cluster-engine (npm) or Socket.IO Cluster-Engine 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

@socket.io/cluster-engine (npm): upgrade to 0.1.1 or later
```
npm install @socket.io/cluster-engine@0.1.1
```

Technical details

The vulnerability exists in @socket.io/cluster-engine versions prior to 0.1.1, where session ID lookups directly access object properties without sanitization, allowing attacker-controlled input like __proto__ or constructor to traverse the prototype chain. The attack requires network access to send malicious session IDs in a clustered deployment, triggering a Node.js process crash. The fix guards client lookups against prototype pollution in version 0.1.1.

Affected products

Socket.IO cluster-engine prior to 0.1.1

Identifiers

CVE-2026-102600
GHSA-wfpm-5gcm-94cg

Timeline

2026-09-29: disclosed
2026-09-08: patched: version 0.1.1 released

References

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