Description
ImpactThe undici WebSocket client is vulnerable to a denial-of-service attack due to improper validation of the server_max_window_bits parameter in the permessage-deflate extension. When a WebSocket client connects to a server, it automatically advertises support for permessage-deflate compression. A malicious server can respond with an out-of-range server_max_window_bits value (outside zlib's valid range of 8-15). When the server subsequently sends a compressed frame, the client attempts to create a zlib InflateRaw instance with the invalid windowBits value, causing a synchronous RangeError exception that is not caught, resulting in immediate process termination.
The vulnerability exists because:
* The isValidClientWindowBits() function only validates that the value contains ASCII digits, not that it falls within the valid range 8-15
* The createInflateRaw() call is not wrapped in a try-catch block
* The resulting exception propagates up through the call stack and crashes the Node.js process
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| undici | undici | < 6.24.0; 7.0.0 < 7.24.0 | 6.24.0: 7.24.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | node-undici | 7.24.5+dfsg+~cs3.2.0-1 | — |
| Debian 13 | node-undici | No fix yet | — |
| Debian 12 | node-undici | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | node-undici | No fix yet | — |
| Ubuntu 26.04 LTS | node-undici | No fix yet | — |
| Ubuntu 25.10 | node-undici | No fix yet | — |
| Ubuntu 24.04 LTS | node-undici | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | nodejs +5 | 1:22.22.2-1.el10_1 | RHSA-2026:7080 |
| RHEL 10 | nodejs-npm | 1:10.9.7-1.22.22.2.1.el10_1 | RHSA-2026:7080 |
| RHEL 10 | nodejs24 +4 | 1:24.14.1-2.el10_1 | RHSA-2026:7675 |
| RHEL 10 | nodejs24-npm | 1:11.11.0-1.24.14.1.2.el10_1 | RHSA-2026:7675 |
| RHEL 9 | nodejs +4 | 1:22.22.2-1.module+el9.7.0+24157+8ddb2461 | RHSA-2026:7350, RHSA-2026:7302 |
| RHEL 9 | nodejs-nodemon | 3.0.1-1.module+el9.7.0+24157+8ddb2461 | RHSA-2026:7350, RHSA-2026:7302 |
| RHEL 9 | nodejs-packaging +1 | 2021.06-6.module+el9.7.0+24157+8ddb2461 | RHSA-2026:7350, RHSA-2026:7302 |
| RHEL 9 | npm | 1:10.9.7-1.22.22.2.1.module+el9.7.0+24157+8ddb2461 | RHSA-2026:7350, RHSA-2026:7302 |
| RHEL 9 | v8-12.4-devel | 3:12.4.254.21-1.22.22.2.1.module+el9.7.0+24157+8ddb2461 | RHSA-2026:7302 |
| RHEL 9 | v8-13.6-devel | 3:13.6.233.17-1.24.14.1.2.module+el9.7.0+24166+51c9666b | RHSA-2026:7350 |
| RHEL 8 | nodejs +4 | 1:22.22.2-1.module+el8.10.0+24148+847b6786 | RHSA-2026:7670, RHSA-2026:7123 |
| RHEL 8 | nodejs-nodemon | 3.0.1-1.module+el8.10.0+24148+847b6786 | RHSA-2026:7670, RHSA-2026:7123 |
| RHEL 8 | nodejs-packaging +1 | 2021.06-6.module+el8.10.0+24148+847b6786 | RHSA-2026:7670, RHSA-2026:7123 |
| RHEL 8 | npm | 1:10.9.7-1.22.22.2.1.module+el8.10.0+24148+847b6786 | RHSA-2026:7670, RHSA-2026:7123 |
| RHEL 8 | v8-12.4-devel | 3:12.4.254.21-1.22.22.2.1.module+el8.10.0+24148+847b6786 | RHSA-2026:7123 |
| RHEL 8 | v8-13.6-devel | 3:13.6.233.17-1.24.14.1.2.module+el8.10.0+24190+49a46c75 | RHSA-2026:7670 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10.0 EUS | nodejs +5 | 1:22.22.2-2.el10_0 | RHSA-2026:7310 |
| RHEL 10.0 EUS | nodejs-npm | 1:10.9.7-1.22.22.2.2.el10_0 | RHSA-2026:7310 |
| RHEL 9.6 EUS | nodejs +4 | 1:22.22.2-1.module+el9.6.0+24196+39669d4e | RHSA-2026:7983 |
| RHEL 9.6 EUS | nodejs-nodemon | 3.0.1-1.module+el9.6.0+23473+45664c2d | RHSA-2026:7983 |
| RHEL 9.6 EUS | nodejs-packaging +1 | 2021.06-4.module+el9.6.0+23473+45664c2d | RHSA-2026:7983 |
| RHEL 9.6 EUS | npm | 1:10.9.7-1.22.22.2.1.module+el9.6.0+24196+39669d4e | RHSA-2026:7983 |
| RHEL 9.6 EUS | v8-12.4-devel | 3:12.4.254.21-1.22.22.2.1.module+el9.6.0+24196+39669d4e | RHSA-2026:7983 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | nodejs-docs | 1:22.22.2-1.el10_1 | ALSA-2026:7080 |
| AlmaLinux 10 | nodejs24-docs | 1:24.14.1-2.el10_1 | ALSA-2026:7675 |
| AlmaLinux 10 | nodejs24-npm | 1:11.11.0-1.24.14.1.2.el10_1 | ALSA-2026:7675 |
| AlmaLinux 9 | nodejs +4 | 1:24.14.1-2.module_el9.7.0+222+ef1c61e1 | ALSA-2026:7350 |
| AlmaLinux 9 | nodejs-nodemon | 3.0.3-3.module_el9.7.0+209+ecf6523e | ALSA-2026:7350 |
| AlmaLinux 9 | nodejs-packaging | 2021.06-6.module_el9.7.0+209+ecf6523e | ALSA-2026:7350 |
| AlmaLinux 9 | nodejs-packaging-bundler | 2021.06-6.module_el9.7.0+198+8bf605ba | ALSA-2026:7350 |
| AlmaLinux 9 | npm | 1:11.11.0-1.24.14.1.2.module_el9.7.0+222+ef1c61e1 | ALSA-2026:7350 |
| AlmaLinux 9 | v8-13.6-devel | 3:13.6.233.17-1.24.14.1.2.module_el9.7.0+222+ef1c61e1 | ALSA-2026:7350 |
| AlmaLinux 8 | nodejs +4 | 1:22.22.2-1.module_el8.10.0+4158+e796f37f | ALSA-2026:7670, ALSA-2026:7123 |
| AlmaLinux 8 | nodejs-nodemon | 3.0.1-1.module_el8.10.0+4006+3c416519 | ALSA-2026:7670, ALSA-2026:7123 |
| AlmaLinux 8 | nodejs-packaging +1 | 2021.06-6.module_el8.10.0+4086+70facd4a | ALSA-2026:7670, ALSA-2026:7123 |
| AlmaLinux 8 | npm | 1:10.9.7-1.22.22.2.1.module_el8.10.0+4158+e796f37f | ALSA-2026:7670, ALSA-2026:7123 |
| AlmaLinux 8 | v8-12.4-devel | 3:12.4.254.21-1.22.22.2.1.module_el8.10.0+4158+e796f37f | ALSA-2026:7123 |
| AlmaLinux 8 | v8-13.6-devel | 3:13.6.233.17-1.24.14.1.2.module_el8.10.0+4160+4819ac42 | ALSA-2026:7670 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | nodejs22 | 1:22.22.2-1.el10_1 | RLSA-2026:7080 |
| Rocky Linux 10 | nodejs24 | 1:24.14.1-2.el10_1 | RLSA-2026:7675 |
| Rocky Linux 9 | nodejs-nodemon | 3.0.1-1.module+el9.7.0+40017+f0db1785 | RLSA-2026:7350, RLSA-2026:7302 |
| Rocky Linux 9 | nodejs-packaging | 2021.06-6.module+el9.7.0+40052+e32ea525 | RLSA-2026:7350, RLSA-2026:7302 |
| Rocky Linux 8 | nodejs-nodemon | 3.0.1-1.module+el8.9.0+1760+903d54b9 | RLSA-2026:7670, RLSA-2026:7123 |
| Rocky Linux 8 | nodejs-packaging | 2021.06-6.module+el8.10.0+40048+6d99f608 | RLSA-2026:7670, RLSA-2026:7123 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | nodejs20 +4 | 1:20.20.1-1.amzn2023.0.3 | ALAS2023-2026-1524 |
| Amazon Linux 2023 | nodejs20-npm | 1:10.8.2-1.20.20.1.1.amzn2023.0.3 | ALAS2023-2026-1524 |
| Amazon Linux 2023 | nodejs22 +4 | 1:22.22.1-1.amzn2023.0.2 | ALAS2023-2026-1525 |
| Amazon Linux 2023 | nodejs22-npm | 1:10.9.4-1.22.22.1.1.amzn2023.0.2 | ALAS2023-2026-1525 |
| Amazon Linux 2023 | nodejs24 +4 | 1:24.14.0-1.amzn2023.0.2 | ALAS2023-2026-1526 |
| Amazon Linux 2023 | nodejs24-npm | 1:11.9.0-1.24.14.0.1.amzn2023.0.2 | ALAS2023-2026-1526 |
| Amazon Linux 2023 | v8-11.3-devel | 3:11.3.244.8-1.20.20.1.1.amzn2023.0.3 | ALAS2023-2026-1524 |
| Amazon Linux 2023 | v8-12.4-devel | 3:12.4.254.21-1.22.22.1.1.amzn2023.0.2 | ALAS2023-2026-1525 |
| Amazon Linux 2023 | v8-13.6-devel | 3:13.6.233.17-1.24.14.0.1.amzn2023.0.2 | ALAS2023-2026-1526 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | nodejs +4 | 1:22.22.2-1.el10_1 | ELSA-2026-7080 |
| Oracle Linux 10 | nodejs-npm | 1:10.9.7-1.22.22.2.1.el10_1 | ELSA-2026-7080 |
| Oracle Linux 10 | nodejs24 +4 | 1:24.14.1-2.0.2.el10_1 | ELSA-2026-7675 |
| Oracle Linux 10 | nodejs24-npm | 1:11.11.0-1.24.14.1.2.0.2.el10_1 | ELSA-2026-7675 |
| Oracle Linux 9 | nodejs +4 | 1:22.22.2-1.module+el9.7.0+90867+2ede48fe | ELSA-2026-7350, ELSA-2026-7302 |
| Oracle Linux 9 | nodejs-nodemon | 3.0.1-1.module+el9.7.0+90867+2ede48fe | ELSA-2026-7350, ELSA-2026-7302 |
| Oracle Linux 9 | nodejs-packaging +1 | 2021.06-6.module+el9.7.0+90866+5a953a4c | ELSA-2026-7350, ELSA-2026-7302 |
| Oracle Linux 9 | npm | 1:10.9.7-1.22.22.2.1.module+el9.7.0+90867+2ede48fe | ELSA-2026-7350, ELSA-2026-7302 |
| Oracle Linux 9 | v8-12.4-devel | 3:12.4.254.21-1.22.22.2.1.module+el9.7.0+90867+2ede48fe | ELSA-2026-7302 |
| Oracle Linux 9 | v8-13.6-devel | 3:13.6.233.17-1.24.14.1.2.module+el9.7.0+90866+5a953a4c | ELSA-2026-7350 |
| Oracle Linux 8 | nodejs +4 | 1:22.22.2-1.module+el8.10.0+90865+d647ef3a | ELSA-2026-7670, ELSA-2026-7123 |
| Oracle Linux 8 | nodejs-nodemon | 3.0.1-1.module+el8.10.0+90865+d647ef3a | ELSA-2026-7670, ELSA-2026-7123 |
| Oracle Linux 8 | nodejs-packaging +1 | 2021.06-4.module+el8.10.0+90865+d647ef3a | ELSA-2026-7670, ELSA-2026-7123 |
| Oracle Linux 8 | npm | 1:10.9.7-1.22.22.2.1.module+el8.10.0+90865+d647ef3a | ELSA-2026-7670, ELSA-2026-7123 |
| Oracle Linux 8 | v8-12.4-devel | 3:12.4.254.21-1.22.22.2.1.module+el8.10.0+90865+d647ef3a | ELSA-2026-7123 |
| Oracle Linux 8 | v8-13.6-devel | 3:13.6.233.17-1.24.14.1.2.module+el8.10.0+90873+35652ecc | ELSA-2026-7670 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | code-server | 4.110.1-r2 | — |
| Wolfi rolling | jitsucom-jitsu-rotor +1 | 2.11.0-r17 | — |
| Wolfi rolling | langfuse-3-worker | 3.179.1-r1 | — |
| Wolfi rolling | renovate | 43.84.0-r1 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| npm | undici | < 6.24.0 | 6.24.0 | GHSA-v9p9-hfj2-hcw8 |
| npm | undici | >= 7.0.0, < 7.24.0 | 7.24.0 | GHSA-v9p9-hfj2-hcw8 |
Advisories 29
- ALSA-2026:7350 Important: nodejs:24 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:7675 Important: nodejs24 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:7080 Important: nodejs22 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:7123 Important: nodejs:22 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:7670 Important: nodejs:24 security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2026:7983 Red Hat Security Advisory: nodejs:22 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:7675 Red Hat Security Advisory: nodejs24 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:7670 Red Hat Security Advisory: nodejs:24 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:7350 Red Hat Security Advisory: nodejs:24 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:7302 Red Hat Security Advisory: nodejs:22 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:7310 Red Hat Security Advisory: nodejs22 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:7123 Red Hat Security Advisory: nodejs:22 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:7080 Red Hat Security Advisory: nodejs22 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- ELSA-2026-7675 Important: nodejs24 security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Jun 9, 2026
- WID-SEC-2026-0933 IBM App Connect Enterprise (Hono und Undici): Mehrere Schwachstellen BSI CERT-Bund (WID) · May 31, 2026
- RLSA-2026:7675 Important: nodejs24 security update Rocky Linux Security Advisories · Apr 15, 2026
- RLSA-2026:7670 Important: nodejs:24 security update Rocky Linux Security Advisories · Apr 13, 2026
- ELSA-2026-7670 Important: nodejs:24 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Apr 13, 2026
- RLSA-2026:7080 Important: nodejs22 security update Rocky Linux Security Advisories · Apr 12, 2026
- RLSA-2026:7350 Important: nodejs:24 security update Rocky Linux Security Advisories · Apr 10, 2026
- ELSA-2026-7350 Important: nodejs:24 security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Apr 10, 2026
- ELSA-2026-7302 Important: nodejs:22 security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Apr 10, 2026
- RLSA-2026:7302 Important: nodejs:22 security update Rocky Linux Security Advisories · Apr 9, 2026
- RLSA-2026:7123 Important: nodejs:22 security update Rocky Linux Security Advisories · Apr 9, 2026
- ELSA-2026-7123 Important: nodejs:22 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Apr 9, 2026
- ELSA-2026-7080 Important: nodejs22 security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Apr 8, 2026
- ALAS2023-2026-1524 Important: nodejs20 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 1, 2026
- ALAS2023-2026-1525 Important: nodejs22 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 1, 2026
- ALAS2023-2026-1526 Important: nodejs24 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 1, 2026