PT-2026-60253 · Debian+3 · Node-Ws+1

George Chen · CVE-2026-62389 · Published 2026-07-15 · Updated 2026-07-15

Positive Technologies (AI Summary)

CVSS v4.0

8.7

High

Base vector

AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Name of the Vulnerable Software and Affected Versions ws versions prior to 8.21.1

Description A memory exhaustion issue exists in lib/receiver.js where the fragment guard only triggers when the fragment count reaches maxFragments. This allows an attacker to cause a denial of service through heap exhaustion by sending incomplete fragmented WebSocket messages. Specifically, an attacker can send a text frame with FIN=0 followed by continuation frames without completing the sequence, which causes each fragment to be stored as a separate Buffer object with significant overhead.

Recommendations Update to version 8.21.1 or later.

Exploit

Fix

Allocation of Resources Without Limits

Weakness Enumeration

CWE-770

Related Identifiers

CVE-2026-62389

Affected Products

Node-Ws

Ws

References · 13

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/62xxx/CVE-2026-62389.json · Exploit
• https://github.com/websockets/ws/commit/f197ac65140920bdcecdab74bfc69c2d7858e55d · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-62389 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-62389 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-62389 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-62389 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-62389 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-62389 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-62389 · Vendor Advisory
• https://github.com/websockets/ws/releases/tag/8.21.1 · Note
• https://github.com/websockets/ws/issues/2331 · Note
• https://github.com/websockets/ws · Note
• https://vulncheck.com/advisories/ws-default-maxfragments-allows-memory-exhaustion-dos · Note