Vulnerability · Published Jun 17, 2026 · Assigned by openjs
CVE-2026-12151undici WebSocket client vulnerable to denial of service via fragment count bypass
High 7.5
In plain English
A high-severity uncontrolled resource consumption in undici from undici. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 56% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.8%top 43.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Impact: The undici WebSocket client enforces maxPayloadSize on the cumulative byte count of fragments in a message but does not enforce a limit on the number of fragments. A malicious WebSocket server can stream many small or empty continuation frames that each pass per-frame and cumulative-size validation, collectively causing unbounded memory growth in the client process. The result is memory exhaustion and a denial of service. Affected applications are those using the undici WebSocket client (new WebSocket(...)) or the WebSocketStream API that can be induced to connect to an attacker-controlled or compromised WebSocket endpoint. All releases starting at undici 6.17.0 are affected. Patches: Upgrade to undici >= 6.26.0, >= 7.28.0, or >= 8.5.0. Workarounds: No workaround is available. The fix must be applied through an upgrade.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:10 | nodejs | 1:22.23.1-2.el10_2 | ALSA-2026:35842 |
| AlmaLinux:8 | nodejs | 1:22.23.1-1.module_el8.10.0+4231+1bf2f855 | ALSA-2026:41947 |
| AlmaLinux:8 | nodejs | 1:24.18.0-1.module_el8.10.0+4228+2938bc94 | ALSA-2026:39868 |
| AlmaLinux:9 | nodejs | 1:22.23.1-1.module_el9.8.0+276+8b329b47 | ALSA-2026:35892 |
| AlmaLinux:9 | nodejs | 1:24.18.0-1.module_el9.8.0+277+61fc613e | ALSA-2026:35891 |
| AlmaLinux:10 | nodejs-devel | 1:22.23.1-2.el10_2 | ALSA-2026:35842 |
| AlmaLinux:8 | nodejs-devel | 1:24.18.0-1.module_el8.10.0+4228+2938bc94 | ALSA-2026:39868 |
| AlmaLinux:8 | nodejs-devel | 1:22.23.1-1.module_el8.10.0+4231+1bf2f855 | ALSA-2026:41947 |
| AlmaLinux:9 | nodejs-devel | 1:22.23.1-1.module_el9.8.0+276+8b329b47 | ALSA-2026:35892 |
| AlmaLinux:9 | nodejs-devel | 1:24.18.0-1.module_el9.8.0+277+61fc613e | ALSA-2026:35891 |
| AlmaLinux:10 | nodejs-docs | 1:22.23.1-2.el10_2 | ALSA-2026:35842 |
| AlmaLinux:8 | nodejs-docs | 1:22.23.1-1.module_el8.10.0+4231+1bf2f855 | ALSA-2026:41947 |
| AlmaLinux:8 | nodejs-docs | 1:24.18.0-1.module_el8.10.0+4228+2938bc94 | ALSA-2026:39868 |
| AlmaLinux:9 | nodejs-docs | 1:24.18.0-1.module_el9.8.0+277+61fc613e | ALSA-2026:35891 |
| AlmaLinux:9 | nodejs-docs | 1:22.23.1-1.module_el9.8.0+276+8b329b47 | ALSA-2026:35892 |
| AlmaLinux:10 | nodejs-full-i18n | 1:22.23.1-2.el10_2 | ALSA-2026:35842 |
| AlmaLinux:8 | nodejs-full-i18n | 1:22.23.1-1.module_el8.10.0+4231+1bf2f855 | ALSA-2026:41947 |
| AlmaLinux:8 | nodejs-full-i18n | 1:24.18.0-1.module_el8.10.0+4228+2938bc94 | ALSA-2026:39868 |
| AlmaLinux:9 | nodejs-full-i18n | 1:22.23.1-1.module_el9.8.0+276+8b329b47 | ALSA-2026:35892 |
| AlmaLinux:9 | nodejs-full-i18n | 1:24.18.0-1.module_el9.8.0+277+61fc613e | ALSA-2026:35891 |
| AlmaLinux:10 | nodejs-libs | 1:22.23.1-2.el10_2 | ALSA-2026:35842 |
| AlmaLinux:8 | nodejs-libs | 1:24.18.0-1.module_el8.10.0+4228+2938bc94 | ALSA-2026:39868 |
| AlmaLinux:8 | nodejs-libs | 1:22.23.1-1.module_el8.10.0+4231+1bf2f855 | ALSA-2026:41947 |
| AlmaLinux:9 | nodejs-libs | 1:24.18.0-1.module_el9.8.0+277+61fc613e | ALSA-2026:35891 |
| AlmaLinux:9 | nodejs-libs | 1:22.23.1-1.module_el9.8.0+276+8b329b47 | ALSA-2026:35892 |
| AlmaLinux:8 | nodejs-nodemon | 3.0.1-1.module_el8.10.0+3956+47c9ee9f | ALSA-2026:41947 |
| AlmaLinux:8 | nodejs-nodemon | 3.0.3-1.module_el8.10.0+4061+f8ceeab9 | ALSA-2026:39868 |
| AlmaLinux:9 | nodejs-nodemon | 3.0.1-1.module_el9.7.0+208+fb06c0ab | ALSA-2026:35892 |
| AlmaLinux:9 | nodejs-nodemon | 3.0.3-3.module_el9.7.0+209+ecf6523e | ALSA-2026:35891 |
| AlmaLinux:10 | nodejs-npm | 1:10.9.8-1.22.23.1.2.el10_2 | ALSA-2026:35842 |
| AlmaLinux:8 | nodejs-packaging | 2021.06-6.module_el8.10.0+4158+e796f37f | ALSA-2026:41947 |
| AlmaLinux:8 | nodejs-packaging | 2021.06-6.module_el8.10.0+4086+70facd4a | ALSA-2026:39868 |
| AlmaLinux:9 | nodejs-packaging | 2021.06-6.module_el9.7.0+227+12323393 | ALSA-2026:35892 |
| AlmaLinux:9 | nodejs-packaging | 2021.06-6.module_el9.7.0+209+ecf6523e | ALSA-2026:35891 |
| AlmaLinux:8 | nodejs-packaging-bundler | 2021.06-6.module_el8.10.0+4158+e796f37f | ALSA-2026:41947 |
| AlmaLinux:8 | nodejs-packaging-bundler | 2021.06-6.module_el8.10.0+4086+70facd4a | ALSA-2026:39868 |
| AlmaLinux:9 | nodejs-packaging-bundler | 2021.06-6.module_el9.7.0+209+ecf6523e | ALSA-2026:35891 |
| AlmaLinux:9 | nodejs-packaging-bundler | 2021.06-6.module_el9.7.0+227+12323393 | ALSA-2026:35892 |
| AlmaLinux:10 | nodejs24 | 1:24.18.0-1.el10_2 | ALSA-2026:35841 |
| AlmaLinux:10 | nodejs24-devel | 1:24.18.0-1.el10_2 | ALSA-2026:35841 |
| AlmaLinux:10 | nodejs24-docs | 1:24.18.0-1.el10_2 | ALSA-2026:35841 |
| AlmaLinux:10 | nodejs24-full-i18n | 1:24.18.0-1.el10_2 | ALSA-2026:35841 |
| AlmaLinux:10 | nodejs24-libs | 1:24.18.0-1.el10_2 | ALSA-2026:35841 |
| AlmaLinux:10 | nodejs24-npm | 1:11.16.0-1.24.18.0.1.el10_2 | ALSA-2026:35841 |
| AlmaLinux:8 | npm | 1:10.9.8-1.22.23.1.1.module_el8.10.0+4231+1bf2f855 | ALSA-2026:41947 |
| AlmaLinux:8 | npm | 1:11.16.0-1.24.18.0.1.module_el8.10.0+4228+2938bc94 | ALSA-2026:39868 |
| AlmaLinux:9 | npm | 1:11.16.0-1.24.18.0.1.module_el9.8.0+277+61fc613e | ALSA-2026:35891 |
| AlmaLinux:9 | npm | 1:10.9.8-1.22.23.1.1.module_el9.8.0+276+8b329b47 | ALSA-2026:35892 |
| AlmaLinux:8 | v8-12.4-devel | 3:12.4.254.21-1.22.23.1.1.module_el8.10.0+4231+1bf2f855 | ALSA-2026:41947 |
| AlmaLinux:9 | v8-12.4-devel | 3:12.4.254.21-1.22.23.1.1.module_el9.8.0+276+8b329b47 | ALSA-2026:35892 |
| AlmaLinux:8 | v8-13.6-devel | 3:13.6.233.17-1.24.18.0.1.module_el8.10.0+4228+2938bc94 | ALSA-2026:39868 |
| AlmaLinux:9 | v8-13.6-devel | 3:13.6.233.17-1.24.18.0.1.module_el9.8.0+277+61fc613e | ALSA-2026:35891 |
| Debian:12 | node-undici | no fix listed | DEBIAN-CVE-2026-12151 |
| Debian:13 | node-undici | no fix listed | DEBIAN-CVE-2026-12151 |
| Debian:14 | node-undici | 8.5.0+dfsg+~cs3.2.0-1 | DEBIAN-CVE-2026-12151 |
| Rocky Linux:8 | nodejs | 1:24.18.0-1.module+el8.10.0+40252+a58646bc | RLSA-2026:39868 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.9.0+1760+903d54b9 | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.10.0+1824+532140ee | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.10.0+1823+b5789597 | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.10.0+1935+d3cbe60f | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.10.0+1989+e60144d9 | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.10.0+1988+437f3d23 | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.10.0+1666+930e28e8 | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.10.0+1924+614dc87f | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.3-1.module+el8.10.0+2084+ab509703 | RLSA-2026:39868 |
| Rocky Linux:8 | nodejs-nodemon | 0:3.0.1-1.module+el8.10.0+1667+4a788d89 | RLSA-2026:41947 |
| Rocky Linux:9 | nodejs-nodemon | 0:3.0.1-1.module+el9.7.0+40022+9ecc286c | RLSA-2026:35892 |
| Rocky Linux:9 | nodejs-nodemon | 0:3.0.1-1.module+el9.7.0+40165+d075e3f2 | RLSA-2026:35892 |
| Rocky Linux:9 | nodejs-nodemon | 0:3.0.1-1.module+el9.7.0+40153+4d595597 | RLSA-2026:35892 |
| Rocky Linux:9 | nodejs-nodemon | 0:3.0.3-3.module+el9.7.0+40025+0e0cf6b2 | RLSA-2026:35891 |
| Rocky Linux:8 | nodejs-packaging | 0:2021.06-6.module+el8.10.0+40172+38f6fdd1 | RLSA-2026:39868 |
| Rocky Linux:8 | nodejs-packaging | 0:2021.06-6.module+el8.10.0+40171+8fa9c325 | RLSA-2026:39868 |
| Rocky Linux:8 | nodejs-packaging | 0:2021.06-6.module+el8.10.0+40048+6d99f608 | RLSA-2026:39868 |
| Rocky Linux:8 | nodejs-packaging | 0:2021.06-6.module+el8.10.0+40048+6d99f608 | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-packaging | 0:2021.06-6.module+el8.10.0+40171+8fa9c325 | RLSA-2026:41947 |
| Rocky Linux:8 | nodejs-packaging | 0:2021.06-6.module+el8.10.0+40172+38f6fdd1 | RLSA-2026:41947 |
| Rocky Linux:9 | nodejs-packaging | 0:2021.06-6.module+el9.7.0+40052+e32ea525 | RLSA-2026:35891 |
| Rocky Linux:9 | nodejs-packaging | 0:2021.06-6.module+el9.7.0+40165+d075e3f2 | RLSA-2026:35891 |
| Rocky Linux:9 | nodejs-packaging | 0:2021.06-6.module+el9.7.0+40153+4d595597 | RLSA-2026:35891 |
| Rocky Linux:9 | nodejs-packaging | 0:2021.06-6.module+el9.7.0+40052+e32ea525 | RLSA-2026:35892 |
| Rocky Linux:9 | nodejs-packaging | 0:2021.06-6.module+el9.7.0+40165+d075e3f2 | RLSA-2026:35892 |
| Rocky Linux:9 | nodejs-packaging | 0:2021.06-6.module+el9.7.0+40153+4d595597 | RLSA-2026:35892 |
| Rocky Linux:10 | nodejs22 | 1:22.23.1-2.el10_2 | RLSA-2026:35842 |
| Rocky Linux:10 | nodejs24 | 1:24.18.0-1.el10_2 | RLSA-2026:35841 |
| Ubuntu:24.04:LTS | node-undici | no fix listed | UBUNTU-CVE-2026-12151 |
| Ubuntu:25.10 | node-undici | no fix listed | UBUNTU-CVE-2026-12151 |
| Ubuntu:26.04:LTS | node-undici | no fix listed | UBUNTU-CVE-2026-12151 |
| Ubuntu:26.10 | node-undici | no fix listed | UBUNTU-CVE-2026-12151 |
| npm | undici | 6.27.0 | GHSA-vxpw-j846-p89q |
| npm | undici | 8.5.0 | GHSA-vxpw-j846-p89q |
| npm | undici | 7.28.0 | GHSA-vxpw-j846-p89q |
Affected products (as reported)
Weakness: CWE-400, CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/nodejs/undici/security/advisories/GHSA-vxpw-j846-p89q
- https://cna.openjsf.org/security-advisories.html
- https://access.redhat.com/security/cve/CVE-2026-12151 vdb-entry, x_refsource_REDHAT
- RHBZ#2489980 issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12151.json x_sadp-csaf-vex
- https://access.redhat.com/errata/RHSA-2026:48151 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:39246 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:35842 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:35841 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:41947 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:39868 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:52399 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:35892 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:35891 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:34342 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:66545 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:66488 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:36754 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:41929 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:38236 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:38009 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:65126 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:60520 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:36621 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:47728 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:48124 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:36820 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:62260 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:56431 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:56366 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:57013 vendor-advisory, x_refsource_REDHAT