CVE catalog
CVE-2026-2229
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 c
- Severity
- High · CVSS 7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.89% · Oct 25, 2026
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
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | node-undici | sid | 8.12.2+dfsg+~cs3.2.3-2 | fixed |
| Debian | node-undici | forky | 8.10.2+dfsg+~cs3.2.2-1 | fixed |
| Debian | node-undici | trixie | 7.3.0+dfsg1+~cs24.12.11-1 | vulnerable |
| Debian | node-undici | bookworm | 5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4 | vulnerable |
| Debian | node-undici | bookworm-security | 5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3 | vulnerable |
| Cpe | node-undici | Not reported | Not reported | vulnerable |
| Npm | undici | Not reported | 6.24.0 | fixed |
| Npm | undici | Not reported | 7.24.0 | fixed |
| Cpe | undici | Not reported | 7.24.0 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | node-undici | source | sid | 7.24.5+dfsg+~cs3.2.0-1 | not yet assigned | Not reported | [1130884] |
| Debian | node-undici | source | forky | 7.24.5+dfsg+~cs3.2.0-1 | not yet assigned | Not reported | [1130884] |
| Debian | node-undici | source | trixie | (unfixed) | not yet assigned | Not reported | [1130884] |
| Debian | node-undici | source | bookworm | (unfixed) | not yet assigned | Not reported | [1130884] |
| Npm | undici | npm | Not reported | 6.24.0 | Not reported | Not reported | Not reported |
| Npm | undici | npm | Not reported | 7.24.0 | Not reported | Not reported | Not reported |
| Cpe | undici | cpe | Not reported | 7.24.0 | Not reported | NVD-CVE-2026-2229 | Not reported |
Notes
[trixie] node-undici: Minor issue [bookworm] node-undici: Minor issue
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [node-llhttp]Affected
Source package: [node-undici]
Details (4)
8.1.0~5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4· all · bookwormAffected
nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
8.1.0~5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4· all · bookwormAffected
nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
8.1.0~5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3· all · bookworm-securityAffected
nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
8.1.0~5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3· all · bookworm-securityAffected
nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
- [node-undici]Affected
Details (4)
5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4· all · bookwormAffected
nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4· all · bookwormAffected
nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3· all · bookworm-securityAffected
nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3· all · bookworm-securityAffected
nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
[Debian 13 (Trixie)]
- [libllhttp9.2]Affected
Source package: [node-undici]
Details (2)
9.2.1~7.3.0+dfsg1+~cs24.12.11-1· amd64 · trixieAffected
nvd · node-undici · debian · 13
9.2.1~7.3.0+dfsg1+~cs24.12.11-1· arm64 · trixieAffected
nvd · node-undici · debian · 13
- [libllhttp-dev]Affected
Source package: [node-undici]
Details (2)
9.2.1~7.3.0+dfsg1+~cs24.12.11-1· amd64 · trixieAffected
nvd · node-undici · debian · 13
9.2.1~7.3.0+dfsg1+~cs24.12.11-1· arm64 · trixieAffected
nvd · node-undici · debian · 13
- [node-llhttp]Affected
Source package: [node-undici]
Details (2)
9.2.1~7.3.0+dfsg1+~cs24.12.11-1· all · trixieAffected
nvd · node-undici · debian · 13
9.2.1~7.3.0+dfsg1+~cs24.12.11-1· all · trixieAffected
nvd · node-undici · debian · 13
- [node-undici]Affected
Details (2)
7.3.0+dfsg1+~cs24.12.11-1· all · trixieAffected
nvd · node-undici · debian · 13
7.3.0+dfsg1+~cs24.12.11-1· all · trixieAffected
nvd · node-undici · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/rhsa-2026_7080.json]
- [https://github.com/advisories/GHSA-v9p9-hfj2-hcw8]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-2229]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-2229]
- [https://security-tracker.debian.org/tracker/CVE-2026-2229]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2229.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-0933.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [GitHub Advisory Database] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]