Resource exhaustion in Node.js Node

CVE-2026-56846

A flaw in Node.js HTTP/2 handling can cause HTTP/2 retained header blocks evade maxSessionMemory and enable remote memory exhaustion.

This vulnerability affects Node.js **24.x** and **22.x**.

Vulnerability class: DoS (Denial of Service)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS 0.005, 43.2th percentile (scored ); unchanged over 30 days. About EPSS.

Affected products

Weakness classification (CWE)

Public exploits and proof-of-concept code

5 public repositories with exploit or proof-of-concept code for this CVE:

  • CompleTech-Security/node-cve-2026-56846-check (last pushed 2026-10-26): Offline Node.js evidence checker for CVE-2026-56846: HTTP/2 retained header memory exhaustion. Single-file Python; JSON/CSV/HTML reports; no exploit payloads.
  • CompleteTech-Security/node-cve-2026-56846-check (last pushed 2026-10-26): Offline Node.js evidence checker for CVE-2026-56846: HTTP/2 retained header memory exhaustion. Single-file Python; JSON/CSV/HTML reports; no exploit payloads.
  • CompleTetech-Security/node-cve-2026-56846-check (last pushed 2026-10-26): Offline Node.js evidence checker for CVE-2026-56846: HTTP/2 retained header memory exhaustion. Single-file Python; JSON/CSV/HTML reports; no exploit payloads.
  • completetech-security/node-cve-2026-56846-check (last pushed 2026-10-24): Standalone defensive checker project for CVE-2026-56846: Node.js: HTTP/2 retained header memory exhaustion. One exploit per repository; implementation pending.
  • CompleteTech-LLC/node-cve-2026-56846-check (last pushed 2026-10-24): Standalone defensive checker project for CVE-2026-56846: Node.js: HTTP/2 retained header memory exhaustion. One exploit per repository; implementation pending.

References

This CVE has public exploit evidence. See the latest CVEs with public exploits.