How severe is GHSA-6663-c963-2gqg?

No CVSS score has been assigned to GHSA-6663-c963-2gqg yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-6663-c963-2gqg?

GHSA-6663-c963-2gqg affects the following packages: ws (npm). Ecosystems affected: npm.

How do I fix GHSA-6663-c963-2gqg?

Update ws to 1.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6663-c963-2gqg is resolved across your whole dependency graph.

How do I detect GHSA-6663-c963-2gqg in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ws, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-6663-c963-2gqg if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is GHSA-6663-c963-2gqg actively exploited in the wild?

No public exploit code has been indexed for GHSA-6663-c963-2gqg yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-6663-c963-2gqg?

GHSA-6663-c963-2gqg has an EPSS (Exploit Prediction Scoring System) score of 7.4%, placing it in the 94th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-6663-c963-2gqg?

GHSA-6663-c963-2gqg is classified as Uncontrolled Resource Consumption (CWE-400), Improper Input Validation (CWE-20). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-6663-c963-2gqg published, and has it been updated?

GHSA-6663-c963-2gqg was published on February 18, 2019 and was last updated on November 8, 2023. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

DoS due to excessively large websocket message in wsGHSA-6663-c963-2gqg

GHSA-6663-c963-2gqg is a Uncontrolled Resource Consumption vulnerability in ws. A fix is available for ws — see the affected versions and patch details below.

Also known asCVE-2016-10542

Published

Feb 18, 2019

Updated

Nov 8, 2023

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

7.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs94th percentile — riskier than 94% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

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.

40Kother npm packages depend on this — each one inherits the vulnerability until it's patched upstream

wsnpm

399.1Mdownloads / week

Description

Affected versions of ws do not appropriately limit the size of incoming websocket payloads, which may result in a denial of service condition when the node process crashes after receiving a large payload.

Recommendation

Update to version 1.1.1 or later. Alternatively, set the maxpayload option for the ws server to a value smaller than 256MB.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`ws`	all versions	1.1.1`npm install ws@1.1.1`

Affected Products

1 product · 1 configurations

Application

wsws_project

≤ 1.1.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ws, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ws to 1.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6663-c963-2gqg is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

Affected versions of `ws` do not appropriately limit the size of incoming websocket payloads, which may result in a denial of service condition when the node process crashes after receiving a large payload. ## Recommendation Update to version 1.1.1 or later. Alternatively, set the `maxpayload` option for the `ws` server to a value smaller than 256MB.