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Fencer Vulns
high 7.5

CVE-2026-56846 json

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

published 2026-08-04 3 mo ago modified 2026-10-23 16 d ago also BIT-node-2026-56846 , BIT-node-min-2026-56846 , EUVD-2026-52564

cvss
7.5
version 3.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits
0
none known

Summary

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**.

Patch / fix

  • bitnami node 22.23.2, 24.18.1
  • bitnami node-min 22.23.2, 24.18.1
  • nodejs node.js 22.23.2, 24.18.1
  • nodejs Debian 12 18.20.4+dfsg-1~deb12u3
  • nodejs Debian 13 20.19.2+dfsg-1+deb13u3
  • nodejs Debian 14 24.19.0+dfsg+~cs24.13.3-1

debian advisories DEBIAN-CVE-2026-56846

  • npm RHEL 8 1:11.17.0-1.24.19.0.1.module+el8.10.0+24711+b610b202
  • nodejs RHEL 8 1:24.19.0-1.module+el8.10.0+24711+b610b202
  • nodejs-libs RHEL 8 1:24.19.0-1.module+el8.10.0+24711+b610b202
  • nodejs-nodemon RHEL 8 3.1.14-2.module+el8.10.0+24711+b610b202
  • nodejs-full-i18n RHEL 8 1:24.19.0-1.module+el8.10.0+24711+b610b202
  • nodejs-packaging RHEL 8 2021.06-6.module+el8.10.0+24711+b610b202
  • nodejs-packaging-bundler RHEL 8 2021.06-6.module+el8.10.0+24711+b610b202
  • npm RHEL 8 1:10.9.8-1.22.23.2.1.module+el8.10.0+24710+c2e9b41f

red hat advisories RHSA-2026:64817RHSA-2026:62583RHSA-2026:62416RHSA-2026:62219RHSA-2026:61386RHSA-2026:61383

  • nodejs16 SLES for SAP 15 SP4, SLES 15 SP4-LTSS, SLE High Performance Computing 15 SP4-LTSS +1 more 16.20.2-150400.3.42.1
  • nodejs18 SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +5 more 18.20.8-150400.9.39.1
  • nodejs20 SLES for SAP 15 SP5, SLES 15 SP5-LTSS, SLE High Performance Computing 15 SP5-LTSS +1 more 20.20.2-150500.11.30.1
  • nodejs22 SLE Module for Web and Scripting 15 SP7 22.23.2-150700.3.18.1
  • nodejs24 SLES 16.0, SLES for SAP applications 16.0 24.18.1-160000.1.1
  • nodejs22 SLES 16.0, SLES for SAP applications 16.0 22.23.2-160000.1.1
  • nodejs24 SLE Module for Web and Scripting 15 SP7 24.18.1-150700.15.16.1
  • nodejs18 SLES LTSS Extended Security 12 SP5, SLES 12 SP5-LTSS 18.20.8-8.44.1

suse advisories SUSE-SU-2026:4355-1SUSE-SU-2026:4261-1SUSE-SU-2026:4248-1SUSE-SU-2026:3930-1SUSE-SU-2026:3929-1SUSE-SU-2026:3557-1

  • nodejs24 openSUSE Leap 16.0 24.18.1-160000.1.1
  • nodejs22 openSUSE Leap 16.0 22.23.2-160000.1.1
  • nodejs24 openSUSE Tumbleweed 24.18.1-1.1
  • nodejs26 openSUSE Tumbleweed 26.5.1-1.1

opensuse advisories openSUSE-SU-2026:21546-1openSUSE-SU-2026:21545-1openSUSE-SU-2026:11439-1openSUSE-SU-2026:11440-1

  • npm AlmaLinux 8 1:11.17.0-1.24.19.0.1.module_el8.10.0+4268+8e07aa5a
  • nodejs AlmaLinux 8 1:24.19.0-1.module_el8.10.0+4268+8e07aa5a
  • nodejs-libs AlmaLinux 8 1:24.19.0-1.module_el8.10.0+4268+8e07aa5a
  • nodejs-nodemon AlmaLinux 8 3.1.14-2.module_el8.10.0+4250+09238ed4
  • nodejs-full-i18n AlmaLinux 8 1:24.19.0-1.module_el8.10.0+4268+8e07aa5a
  • nodejs-packaging AlmaLinux 8 2021.06-6.module_el8.10.0+4086+70facd4a
  • nodejs-packaging-bundler AlmaLinux 8 2021.06-6.module_el8.10.0+4086+70facd4a
  • npm AlmaLinux 8 1:10.9.8-1.22.23.2.1.module_el8.10.0+4265+75d28086

almalinux advisories ALSA-2026:62583ALSA-2026:62219ALSA-2026:61376ALSA-2026:61377ALSA-2026:61383ALSA-2026:61386

  • nodejs-nodemon Rocky Linux 8 3.1.14-2.module+el8.10.0+40277+b1b3f89e
  • nodejs-nodemon Rocky Linux 8 3.1.14-2.module+el8.10.0+40278+50b003a3
  • nodejs-packaging Rocky Linux 8 2021.06-6.module+el8.10.0+40172+38f6fdd1
  • nodejs-packaging Rocky Linux 8 2021.06-6.module+el8.10.0+40171+8fa9c325
  • nodejs-packaging Rocky Linux 8 2021.06-6.module+el8.10.0+40048+6d99f608
  • nodejs22 Rocky Linux 10 1:22.23.2-1.el10_2
  • nodejs24 Rocky Linux 10 1:24.19.0-1.el10_2
  • nodejs Rocky Linux 8 1:22.23.2-1.module+el8.10.0+40306+15f89705

rocky linux advisories RLSA-2026:62583RLSA-2026:61376RLSA-2026:61377RLSA-2026:62219RLSA-2026:61383RLSA-2026:61386

  • nodejs Alpine 3.22, Alpine 3.21 22.23.2-r0
  • nodejs Alpine 3.24, Alpine 3.23 24.18.1-r0

alpine advisories ALPINE-CVE-2026-56846

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-56846 updated cvss 7.5

nodejs: Node.js: Remote memory exhaustion via HTTP/2 retained header blocks

  • Red Hat Enterprise Linux 9 npm, nodejs, nodejs-libs, nodejs-full-i18n
    affected: workaround, no fix available
  • Red Hat Enterprise Linux AppStream (v. 8) nodejs 22.23.2-1.module+el8.10.0+24710+c2e9b41f, nodejs 24.19.0-1.module+el8.10.0+24711+b610b202, nodejs-libs 22.23.2-1.module+el8.10.0+24710+c2e9b41f, nodejs-libs 24.19.0-1.module+el8.10.0+24711+b610b202, npm 10.9.8-1.22.23.2.1.module+el8.10.0+24710+c2e9b41f, nodejs-nodemon 3.1.14-2.module+el8.10.0+24710+c2e9b41f, +8 more
    fixed: vendor fix RHSA-2026:62219
  • Red Hat Enterprise Linux AppStream (v. 9) nodejs 22.23.2-1.module+el9.8.0+24709+804d6b5b, nodejs 24.19.0-1.module+el9.8.0+24708+e71d2e1d, nodejs-libs 22.23.2-1.module+el9.8.0+24709+804d6b5b, nodejs-libs 24.19.0-1.module+el9.8.0+24708+e71d2e1d, npm 10.9.8-1.22.23.2.1.module+el9.8.0+24709+804d6b5b, nodejs-nodemon 3.1.14-2.module+el9.8.0+24709+804d6b5b, +8 more
    fixed: vendor fix RHSA-2026:61383
  • Red Hat Enterprise Linux AppStream (v. 10) nodejs 22.23.2-1.el10_2, nodejs22 22.23.2-1.el10_2, nodejs24 24.19.0-1.el10_2, nodejs-libs 22.23.2-1.el10_2, nodejs24-libs 24.19.0-1.el10_2, nodejs-full-i18n 22.23.2-1.el10_2, +3 more
    fixed: vendor fix RHSA-2026:61376
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0) nodejs 22.23.2-1.el10_0, nodejs22 22.23.2-1.el10_0, nodejs-libs 22.23.2-1.el10_0, nodejs-full-i18n 22.23.2-1.el10_0, nodejs-npm 10.9.8-1.22.23.2.1.el10_0
    fixed: vendor fix RHSA-2026:64817
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) nodejs 22.23.2-1.module+el9.6.0+24769+299a7e3a, nodejs-libs 22.23.2-1.module+el9.6.0+24769+299a7e3a, npm 10.9.8-1.22.23.2.1.module+el9.6.0+24769+299a7e3a, nodejs-nodemon 3.1.14-2.module+el9.6.0+24789+4011c12f, nodejs-full-i18n 22.23.2-1.module+el9.6.0+24769+299a7e3a, nodejs-packaging 2021.06-4.module+el9.6.0+23473+45664c2d, +1 more
    fixed: vendor fix RHSA-2026:62416
  • Red Hat Hardened Images nodejs22 22.23.2-2.3.hum1, nodejs24 24.18.1-0.1.hum1, nodejs22-bin 22.23.2-2.3.hum1, nodejs24-bin 24.18.1-0.1.hum1, nodejs22-libs 22.23.2-2.3.hum1, nodejs24-libs 24.18.1-0.1.hum1, +6 more
    fixed: vendor fix RHSA-2026:48305
  • Red Hat Hardened Images nodejs20, nodejs25, nodejs26
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.50% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.0 7.5 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV 3.0 7.5 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
bitnami node
<22.23.2
>=23.0.0, <24.18.1
22.23.2
24.18.1
bitnami node-min
<22.23.2
>=23.0.0, <24.18.1
22.23.2
24.18.1

Affected products

  • nodejs node

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.