Improper handling of highly compressed data in undici - CVE-2026-1526

Vulnerability identifier: #VU127576

CSH Severity: Medium

CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-1526

CWE-ID: CWE-409

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper handling of highly compressed data in PerMessageDeflate.decompress() when decompressing incoming WebSocket frames negotiated with the permessage-deflate extension. A remote attacker can send a specially crafted compressed WebSocket frame to cause a denial of service.

Memory exhaustion occurs in native or external memory and can cause the Node.js process to crash or become unresponsive.

undici
IBM Cloud Pak System
DataStage on Cloud Pak for Data
Platform Navigator in IBM Cloud Pak for Integration (CP4I)
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Fedora
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
nodejs20
nodejs22 (Red Hat package)
nodejs22
nodejs24 (Red Hat package)

Install security update from vendor's website.

undici - addressed in versions 6.24.0, 7.24.0
IBM Cloud Pak System - update to 2.3.5.1
DataStage on Cloud Pak for Data - update to 5.4
Platform Navigator in IBM Cloud Pak for Integration (CP4I) - addressed in versions 16.1.0.23, 16.1.3.6
nodejs20 - update to 20.20.2-3.fc43
nodejs22 (Red Hat package) - addressed in versions 22.22.2-1.el10_1, 22.22.2-2.el10_0
nodejs22 - addressed in versions 22.22.2-2.fc43, 22.22.2-3.fc42, 22.22.2-3.fc44
nodejs24 (Red Hat package) - update to 24.14.1-2.el10_1

• https://github.com/nodejs/undici/security/advisories/GHSA-vrm6-8vpv-qv8q

• Multiple vulnerabilities in undici
• Fedora 43 update for nodejs20
• Red Hat Enterprise Linux 10 update for nodejs22
• Red Hat Enterprise Linux 8 update for the nodejs:22 module
• Red Hat Enterprise Linux 9 update for the nodejs:22 module
• Red Hat Enterprise Linux 10 update for nodejs22
• Red Hat Enterprise Linux 9 update for the nodejs:24 module
• Red Hat Enterprise Linux 10 update for nodejs24
• Red Hat Enterprise Linux 9 update for the nodejs:22 module
• Fedora 44 update for nodejs22
• Fedora 43 update for nodejs22
• Multiple vulnerabilities in IBM Platform Navigator in IBM Cloud Pak for Integration (CP4I)
• Fedora 42 update for nodejs22
• Multiple vulnerabilities in IBM DataStage on Cloud Pak for Data
• Multiple vulnerabilities in IBM Cloud Pak System Software