GHSA-r7qp-cfhv-p84w is a medium-severity (CVSS 6.5) CWE-248 vulnerability in engine.io. 1 public exploit reference exists, so weaponization risk is real. A fix is available for engine.io — see the affected versions and patch details below.
Uncaught exception in engine.io
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-r7qp-cfhv-p84w plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
engine.ionpmDescription
Impact
A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process.
events.js:292
throw er; // Unhandled 'error' event
^
Error: read ECONNRESET
at TCP.onStreamRead (internal/stream_base_commons.js:209:20)
Emitted 'error' event on Socket instance at:
at emitErrorNT (internal/streams/destroy.js:106:8)
at emitErrorCloseNT (internal/streams/destroy.js:74:3)
at processTicksAndRejections (internal/process/task_queues.js:80:21) {
errno: -104,
code: 'ECONNRESET',
syscall: 'read'
}
This impacts all the users of the engine.io package, including those who uses depending packages like socket.io.
Patches
A fix has been released today (2022/11/20):
| Version range | Fixed version |
|---|---|
[email protected] | 3.6.1 |
[email protected] | 6.2.1 |
For socket.io users:
| Version range | engine.io version | Needs minor update? |
|---|---|---|
[email protected] | ~6.2.0 | npm audit fix should be sufficient |
[email protected] | ~6.1.0 | Please upgrade to [email protected] |
[email protected] | ~6.0.0 | Please upgrade to [email protected] |
[email protected] | ~5.2.0 | Please upgrade to [email protected] |
[email protected] | ~5.1.1 | Please upgrade to [email protected] |
[email protected] | ~5.0.0 | Please upgrade to [email protected] |
[email protected] | ~4.1.0 | Please upgrade to [email protected] (see here) |
[email protected] | ~4.0.0 | Please upgrade to [email protected] (see here) |
[email protected] | ~3.6.0 | npm audit fix should be sufficient |
[email protected] and below | ~3.5.0 | Please upgrade to [email protected] |
Workarounds
There is no known workaround except upgrading to a safe version.
For more information
If you have any questions or comments about this advisory:
- Open an issue in
engine.io
Thanks to Jonathan Neve for the responsible disclosure.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | engine.io | all versions | 3.6.1npm install engine.io@3.6.1 |
| 📦npm | engine.io | ≥ 4.0.0&&< 6.2.1 | 6.2.1npm install engine.io@6.2.1 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for engine.io, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update engine.io to 3.6.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r7qp-cfhv-p84w is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-r7qp-cfhv-p84w can be triaged on real exposure rather than presence alone.
Tailored to GHSA-r7qp-cfhv-p84w. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Fuse 7.12 | engine.io | RHSA-2023:3954 |
Frequently Asked Questions
Is GHSA-r7qp-cfhv-p84w in your dependencies?
O3 Security finds GHSA-r7qp-cfhv-p84w across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.