CVE-2026-56848

nodejs: Node.js: Heap-use-after-free in HTTP/2 handling can lead to denial of service

Published Aug 4, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
A flaw in Node.js HTTP/2 handling allows `nghttp2_session_mem_send()` to be called re-entrantly while `nghttp2_session_mem_recv()` is executing, resulting in a heap-use-after-free.

This vulnerability affects Node.js **26.x**, **24.x**, and **22.x**.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4809-1 nodejs security update
Debian DSA Debian DSA DSA-6517-1 nodejs security update
History
Type Values Removed Values Added
Title Node.js HTTP/2 Heap Use‑After‑Free via Re‑entrant Call nodejs: Node.js: Heap-use-after-free in HTTP/2 handling can lead to denial of service
Weaknesses CWE-825
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Important

Type Values Removed Values Added
First Time appeared Nodejs
Nodejs nodejs
Vendors & Products Nodejs
Nodejs nodejs
Type Values Removed Values Added
Title Node.js HTTP/2 Heap Use‑After‑Free via Re‑entrant Call
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description A flaw in Node.js HTTP/2 handling allows `nghttp2_session_mem_send()` to be called re-entrantly while `nghttp2_session_mem_recv()` is executing, resulting in a heap-use-after-free. This vulnerability affects Node.js **26.x**, **24.x**, and **22.x**.
Weaknesses CWE-416
References
Metrics cvssV3_0

{'score': 7.5, 'vector': 'CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
hackerone
Published
Updated
Aug 4, 2026, 5:36 PM
Reserved
Jun 23, 2026, 3:00 PM
Status
Awaiting Analysis
Published
Aug 4, 2026, 5:16 PM
Modified
Oct 24, 2026, 4:10 PM
Severity
Important
Public date
Aug 4, 2026, 3:57 PM