Nodejs: 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,… (CVE-2026-56848)
Description
A vulnerability in Node.js HTTP/2 handling allows the function nghttp2_session_mem_send() to be called re-entrantly while nghttp2_session_mem_recv() is executing, leading to a heap-use-after-free condition. This affects Node.js versions 22.x, 24.x, and 26.x. The issue can cause a denial of service due to application crashes but does not impact confidentiality or integrity.
CVSS v3.0
Score 7.5high
Affected software
pkg:deb/ubuntu/nodejs?arch=source&distro=esm-infra-legacy/trustypkg:deb/ubuntu/nodejs?arch=source&distro=esm-apps/xenialpkg:deb/ubuntu/nodejs?arch=source&distro=esm-apps/bionicpkg:deb/ubuntu/nodejs?arch=source&distro=esm-apps/focalpkg:deb/ubuntu/nodejs?arch=source&distro=esm-apps/jammypkg:deb/ubuntu/nodejs?arch=source&distro=noblepkg:deb/ubuntu/nodejs?arch=source&distro=stonkingpkg:deb/ubuntu/nodejs?arch=source&distro=resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The flaw in Node.js HTTP/2 implementation involves improper handling of re-entrant calls between nghttp2_session_mem_send() and nghttp2_session_mem_recv(), resulting in a heap-use-after-free vulnerability. This memory corruption can cause application instability or crashes. The vulnerability affects Node.js versions 22.x, 24.x, and 26.x as explicitly stated. The CVSS 3.0 score is 7.5, reflecting a network attack vector with low complexity and no privileges required, causing availability impact only.
Potential Impact
Successful exploitation can lead to denial of service by crashing the Node.js process due to heap-use-after-free memory corruption. There is no impact on confidentiality or integrity according to the CVSS vector. No known exploits in the wild have been reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Users should monitor vendor advisories for updates and apply patches once available.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-56848
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:Pro:14.04:LTS","Ubuntu:Pro:16.04:LTS","Ubuntu:Pro:18.04:LTS","Ubuntu:Pro:20.04:LTS","Ubuntu:Pro:22.04:LTS","Ubuntu:24.04:LTS","Ubuntu:26.10","Ubuntu:26.04:LTS"]
- Cvss Version
- 3.0
- State
- PUBLISHED
Threat ID: 6ad3f5e72cdf04f6566634d9
Added to database: 10/17/2026, 22:25:43 UTC
Last enriched: 10/18/2026, 00:35:54 UTC
Last updated: 10/18/2026, 00:35:54 UTC
Views: 2
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