CVE-2016-10544 is a medium-severity (CVSS 5.9) Uncontrolled Resource Consumption vulnerability in uws. A fix is available for uws — see the affected versions and patch details below.
Denial of Service in uws
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2016-10544 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
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.
uwsnpmDescription
Affected versions of uws do not properly handle large websocket messages when permessage-deflate is enabled, which may result in a denial of service condition.
If uws recieves a 256Mb websocket message when permessage-deflate is enabled, the server will compress the message prior to executing the length check, and subsequently extract the message prior to processing. This can result in a situation where an excessively large websocket message passes the length checks, yet still gets cast from a Buffer to a string, which will exceed v8's maximum string size and crash the process.
Recommendation
Update to version 0.10.9 or later.
Alternatively, disable permessage-deflate.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | uws | ≥ 0.10.0&&< 0.10.9 | 0.10.9npm install uws@0.10.9 |
Affected Products
uwsuws_projectDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for uws, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update uws to 0.10.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-10544 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
Is CVE-2016-10544 in your dependencies?
Find it across npm, including transitive dependencies.