What is CVE-2026-62389?

CVE-2026-62389 is a high-severity vulnerability in Websockets Ws, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-07-15.

How severe is CVE-2026-62389?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Websockets Ws

CVE-2026-62389

ws before 8.21.1 contains a memory exhaustion vulnerability in lib/receiver.js where the fragment guard only triggers when fragment count reaches maxFragments, allowing attackers to exhaust memory by sending incomplete fragmented WebSocket…

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Websockets Ws — versions 0

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

disclosure@vulncheck.com (technical-description)
disclosure@vulncheck.com (release-notes)
disclosure@vulncheck.com (patch)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-62389?: CVE-2026-62389 is a high-severity vulnerability in Websockets Ws, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-07-15.
How severe is CVE-2026-62389?: High severity. CVSS v3 base score is 7.5 out of 10.