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Fencer Vulns
high 7.5

CVE-2026-21710 in the critical feed json

A flaw in Node.js HTTP request handling causes an uncaught `TypeError` when a request is received with a header named `__proto__` and the a…

published 2026-03-30 7 mo ago modified 2026-09-08 2 mo ago also BIT-node-2026-21710 , BIT-node-min-2026-21710 , EUVD-2026-17170

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
25.4%
EPSS 25.4% chance of exploitation in 30 days, percentile 97%
public exploits
0
none known

Summary

A flaw in Node.js HTTP request handling causes an uncaught `TypeError` when a request is received with a header named `__proto__` and the application accesses `req.headersDistinct`.

When this occurs, `dest["__proto__"]` resolves to `Object.prototype` rather than `undefined`, causing `.push()` to be called on a non-array. This exception is thrown synchronously inside a property getter and cannot be intercepted by `error` event listeners, meaning it cannot be handled without wrapping every `req.headersDistinct` access in a `try/catch`.

* This vulnerability affects all Node.js HTTP servers on **20.x, 22.x, 24.x, and v25.x**

Patch / fix

  • bitnami node 20.20.2, 22.22.2, 24.14.1, 25.8.2
  • bitnami node-min 20.20.2, 22.22.2, 24.14.1, 25.8.2
  • Red Hat Red Hat Enterprise Linux 10 1:22.22.2-1.el10_1, 1:24.14.1-2.el10_1
  • Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support 1:22.22.2-2.el10_0
  • Red Hat Red Hat Enterprise Linux 8 8100020260331102257.6d880403, 8100020260408131901.6d880403, 8100020260414073138.489197e6
  • Red Hat Red Hat Enterprise Linux 9 9070020260401095228.rhel9, 9070020260402152654.rhel9, 9070020260409073121.rhel9
  • Red Hat Red Hat Enterprise Linux 9.4 Extended Update Support 9040020260421133644.rhel9
  • Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support 9060020260409121057.rhel9, 9060020260422064119.rhel9
  • nodejs Debian 12 18.20.4+dfsg-1~deb12u2
  • nodejs Debian 13 20.19.2+dfsg-1+deb13u2
  • nodejs Debian 14 22.22.2+dfsg+~cs22.19.15-1

debian advisories DEBIAN-CVE-2026-21710

  • npm RHEL 8 1:10.8.2-1.20.20.2.1.module+el8.10.0+24197+1602b452
  • nodejs RHEL 8 1:20.20.2-1.module+el8.10.0+24197+1602b452
  • nodejs-nodemon RHEL 8 3.0.1-1.module+el8.10.0+23521+490ebfde
  • nodejs-full-i18n RHEL 8 1:20.20.2-1.module+el8.10.0+24197+1602b452
  • nodejs-packaging RHEL 8 2021.06-6.module+el8.10.0+24197+1602b452
  • nodejs-packaging-bundler RHEL 8 2021.06-6.module+el8.10.0+24197+1602b452
  • npm RHEL 9 1:10.8.2-1.20.20.2.1.module+el9.7.0+24193+41b7b572
  • nodejs RHEL 9 1:20.20.2-1.module+el9.7.0+24193+41b7b572

red hat advisories RHSA-2026:9874RHSA-2026:9711RHSA-2026:8339RHSA-2026:7983RHSA-2026:7896RHSA-2026:7675

  • 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
  • nodejs22 SLES for SAP applications 16.0, SLES 16.0 22.23.0-160000.1.1
  • nodejs22 SLE Module for Web and Scripting 15 SP7 22.22.2-150700.3.9.1
  • nodejs20 SLES for SAP 15 SP5, SLES 15 SP5-LTSS, SLE High Performance Computing 15 SP5-LTSS +1 more 20.20.2-150500.11.27.1
  • nodejs24 SLE Module for Web and Scripting 15 SP7 24.14.1-150700.15.8.1
  • nodejs24 SLES for SAP applications 16.0, SLES 16.0 24.14.1-160000.1.1
  • 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-2026:22368-1SUSE-SU-2026:1509-1SUSE-SU-2026:1478-1

  • nodejs22 openSUSE Leap 16.0 22.23.0-160000.1.1
  • nodejs26 openSUSE Tumbleweed 26.3.1-1.1
  • nodejs24 openSUSE Leap 16.0 24.14.1-160000.1.1
  • nodejs24 openSUSE Tumbleweed 24.14.1-1.1

opensuse advisories openSUSE-SU-2026:21058-1openSUSE-SU-2026:11110-1openSUSE-SU-2026:20519-1openSUSE-SU-2026:10504-1

  • npm AlmaLinux 8 1:10.8.2-1.20.20.2.1.module_el8.10.0+4165+3f200bda
  • nodejs AlmaLinux 8 1:20.20.2-1.module_el8.10.0+4165+3f200bda
  • nodejs-nodemon AlmaLinux 8 3.0.1-1.module_el8.10.0+3982+85c136aa
  • nodejs-full-i18n AlmaLinux 8 1:20.20.2-1.module_el8.10.0+4165+3f200bda
  • nodejs-packaging AlmaLinux 8 2021.06-6.module_el8.10.0+4165+3f200bda
  • nodejs-packaging-bundler AlmaLinux 8 2021.06-6.module_el8.10.0+4165+3f200bda
  • npm AlmaLinux 8 1:11.11.0-1.24.14.1.2.module_el8.10.0+4160+4819ac42
  • nodejs AlmaLinux 8 1:24.14.1-2.module_el8.10.0+4160+4819ac42

almalinux advisories ALSA-2026:8339ALSA-2026:7670ALSA-2026:7675ALSA-2026:7896ALSA-2026:7350ALSA-2026:7123

  • nodejs-nodemon Rocky Linux 8 3.0.1-1.module+el8.10.0+1924+614dc87f
  • nodejs-nodemon Rocky Linux 8 3.0.1-1.module+el8.10.0+1935+d3cbe60f
  • nodejs-nodemon Rocky Linux 8 3.0.1-1.module+el8.10.0+1666+930e28e8
  • nodejs-nodemon Rocky Linux 8 3.0.1-1.module+el8.10.0+1667+4a788d89
  • nodejs-nodemon Rocky Linux 8 3.0.1-1.module+el8.10.0+1989+e60144d9
  • nodejs-nodemon Rocky Linux 8 3.0.1-1.module+el8.10.0+1988+437f3d23
  • nodejs-nodemon Rocky Linux 8 3.0.1-1.module+el8.9.0+1760+903d54b9
  • nodejs-nodemon Rocky Linux 8 3.0.1-1.module+el8.10.0+1823+b5789597

rocky linux advisories RLSA-2026:8339RLSA-2026:7675RLSA-2026:7896RLSA-2026:7670RLSA-2026:7080RLSA-2026:7350

  • nodejs Alpine 3.22, Alpine 3.21 22.22.2-r0
  • nodejs Alpine 3.24, Alpine 3.23 24.14.1-r0

alpine advisories ALPINE-CVE-2026-21710

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

  • nodejs Azure Linux 3.0 20.14.0-15
  • nodejs24 Azure Linux 3.0 24.14.1-1

azure linux advisories AZL-81239AZL-81257

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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-2026-21710 updated cvss 7.5

Node.js: Node.js: Denial of Service due to crafted HTTP `__proto__` header

  • Red Hat Enterprise Linux AppStream (v. 8) nodejs 20.20.2-1.module+el8.10.0+24197+1602b452, nodejs 22.22.2-1.module+el8.10.0+24148+847b6786, nodejs 24.14.1-2.module+el8.10.0+24190+49a46c75, nodejs-libs 22.22.2-1.module+el8.10.0+24148+847b6786, nodejs-libs 24.14.1-2.module+el8.10.0+24190+49a46c75, nodejs-nodemon 3.0.1-1.module+el8.10.0+23521+490ebfde, +14 more
    fixed: vendor fix RHSA-2026:8339
  • Red Hat Enterprise Linux AppStream (v. 9) nodejs 20.20.2-1.module+el9.7.0+24193+41b7b572, nodejs 22.22.2-1.module+el9.7.0+24157+8ddb2461, nodejs 24.14.1-2.module+el9.7.0+24166+51c9666b, nodejs-libs 22.22.2-1.module+el9.7.0+24157+8ddb2461, nodejs-libs 24.14.1-2.module+el9.7.0+24166+51c9666b, nodejs-nodemon 3.0.1-1.module+el9.7.0+24157+8ddb2461, +14 more
    fixed: vendor fix RHSA-2026:7896
  • Red Hat Enterprise Linux AppStream (v. 10) nodejs 22.22.2-1.el10_1, nodejs22 22.22.2-1.el10_1, nodejs24 24.14.1-2.el10_1, nodejs-libs 22.22.2-1.el10_1, nodejs24-libs 24.14.1-2.el10_1, nodejs-full-i18n 22.22.2-1.el10_1, +3 more
    fixed: vendor fix RHSA-2026:7080
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0) nodejs 22.22.2-2.el10_0, nodejs22 22.22.2-2.el10_0, nodejs-libs 22.22.2-2.el10_0, nodejs-full-i18n 22.22.2-2.el10_0, nodejs-npm 10.9.7-1.22.22.2.2.el10_0
    fixed: vendor fix RHSA-2026:7310
  • Red Hat Enterprise Linux AppStream EUS (v.9.4) nodejs 20.20.2-2.module+el9.4.0+24216+64c58546, npm 10.8.2-1.20.20.2.2.module+el9.4.0+24216+64c58546, nodejs-nodemon 3.0.1-1.module+el9.3.0.z+20478+84a9f781, nodejs-full-i18n 20.20.2-2.module+el9.4.0+24216+64c58546, nodejs-packaging 2021.06-4.module+el9.3.0+19518+63aad52d, nodejs-packaging-bundler 2021.06-4.module+el9.3.0+19518+63aad52d
    fixed: vendor fix RHSA-2026:9711
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) nodejs 20.20.2-2.module+el9.6.0+24220+c44c288d, nodejs 22.22.2-1.module+el9.6.0+24196+39669d4e, nodejs-libs 22.22.2-1.module+el9.6.0+24196+39669d4e, nodejs-nodemon 3.0.1-1.module+el9.6.0+23146+be9976bd, nodejs-nodemon 3.0.1-1.module+el9.6.0+23473+45664c2d, npm 10.8.2-1.20.20.2.2.module+el9.6.0+24220+c44c288d, +7 more
    fixed: vendor fix RHSA-2026:9874

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
7 mo ago

Exploit prediction

25.44% chance of exploitation in the next 30 days, higher than 97% 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
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV 3.1 7.5 CVSS:3.1/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
<20.20.2
>=21.0.0, <22.22.2
>=23.0.0, <24.14.1
>=25.0.0, <25.8.2
20.20.2
22.22.2
24.14.1
25.8.2
bitnami node-min
<20.20.2
>=21.0.0, <22.22.2
>=23.0.0, <24.14.1
>=25.0.0, <25.8.2
20.20.2
22.22.2
24.14.1
25.8.2

Affected products

  • nodejs node
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Enterprise Linux 9.4 Extended Update Support
  • Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support

Classification

Weakness
  • CWE-770 Allocation of Resources Without Limits or Throttling
  • CWE-843 Access of Resource Using Incompatible Type
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.