PatchTheCVECVE-2026-56848: A flaw in Node.js HTTP/2 handling allows `nghttp2_session_mem_send()` to be called re-entrantly while `nghttp2
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HIGH 7.5REMOTE
CVE-2026-56848 is a high-severity flaw (CVSS 7.5) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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**.
Why this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.5 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.5% (top 59%) |
| CISA exploited list | No |
| Weakness | CWE-416 |
| Published | 2026-08-04 |
| Last modified | 2026-10-23 |
Publisher (CNA): HackerOne
Timeline
- Published CVE record published
- Updated Record last modified
Exact fixes by distribution
Fedora 46 · kwin-zones · FIXED · 1.0.13-1.fc46 · FEDORA-2026-95888f332b · source
sudo dnf upgrade --advisory=FEDORA-2026-95888f332b
Fedora ELN · nginx-mod-brotli · FIXED · 1.0.0~rc-16.eln159 · FEDORA-2026-501a6a8273 · source
sudo dnf upgrade --advisory=FEDORA-2026-501a6a8273
Debian 12 · nodejs · FIXED · 18.20.4+dfsg-1~deb12u3
sudo apt update && sudo apt install --only-upgrade nodejs
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' nodejs)" ge "18.20.4+dfsg-1~deb12u3" && echo PATCHED || echo STILL-VULNERABLE
Debian 13 · nodejs · FIXED · 20.19.2+dfsg-1+deb13u3
sudo apt update && sudo apt install --only-upgrade nodejs
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' nodejs)" ge "20.19.2+dfsg-1+deb13u3" && echo PATCHED || echo STILL-VULNERABLE
RHEL 10 · nodejs22 · FIXED · nodejs22-22.23.2-1.el10_2
sudo dnf upgrade --advisory=RHSA-2026:61376
rpm -q nodejs22
RHEL 10 · nodejs24 · FIXED · nodejs24-24.19.0-1.el10_2
sudo dnf upgrade --advisory=RHSA-2026:61377
rpm -q nodejs24
RHEL 10.0 Extended Update Support · nodejs22 · FIXED · nodejs22-22.23.2-1.el10_0
sudo dnf upgrade --advisory=RHSA-2026:64817
rpm -q nodejs22
RHEL 10 · nodejs26 · NO FIX YET
RHEL 9 · nodejs:26/nodejs · NO FIX YET
Alpine 3.21 · nodejs · FIXED · nodejs-22.23.2-r0
apk add --upgrade nodejs
apk info -v nodejs
Alpine 3.22 · nodejs · FIXED · nodejs-22.23.2-r0
apk add --upgrade nodejs
apk info -v nodejs
Alpine 3.23 · nodejs · FIXED · nodejs-24.18.1-r0
apk add --upgrade nodejs
apk info -v nodejs
Alpine 3.24 · nodejs · FIXED · nodejs-24.18.1-r0
apk add --upgrade nodejs
apk info -v nodejs
sudo dnf update --advisory=ALAS2023-2026-2060
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- GitHub PoC: open-flaw/CVE-2026-56848 (0 stars)
- GitHub PoC: completetech-security/node-cve-2026-56848-check (0 stars)
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.