CRLF injection in undici - CVE-2026-1527

Vulnerability identifier: #VU127577

CSH Severity: Low

CVSS v4: 2.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-1527

CWE-ID: CWE-93

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to inject arbitrary HTTP headers and smuggle raw data to non-HTTP services.

The vulnerability exists due to improper neutralization of CRLF sequences in the upgrade option of client.request() when processing user-controlled input. A remote attacker can supply a specially crafted upgrade value to inject arbitrary HTTP headers and smuggle raw data to non-HTTP services.

User interaction is required because an application must pass user-controlled input to the upgrade option.

undici
IBM Cloud Pak System
DataStage on Cloud Pak for Data
Platform Navigator in IBM Cloud Pak for Integration (CP4I)
Netezza Appliance - Cyclops
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Fedora
IBM Maximo Application Suite
Informix Dynamic Server
nodejs20
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
IBM Maximo Application Suite - addressed in versions 9.0.29, 9.1.21, 9.2.2
Platform Navigator in IBM Cloud Pak for Integration (CP4I) - addressed in versions 16.1.0.23, 16.1.3.6
Netezza Appliance - Cyclops - update to 11.3.1.4
Informix Dynamic Server - addressed in versions 14.10.FC14W1, 15.0.1.16
nodejs20 - update to 20.20.2-3.fc43
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-4992-7rv2-5pvq
• https://github.com/advisories/GHSA-4992-7rv2-5pvq

• Multiple vulnerabilities in undici
• Fedora 43 update for nodejs20
• Red Hat Enterprise Linux 9 update for the nodejs:24 module
• Red Hat Enterprise Linux 10 update for nodejs24
• 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
• Multiple vulnerabilities in IBM Maximo Application Suite
• Multiple vulnerabilities in IBM Netezza Appliance - Cyclops
• Multiple vulnerabilities in IBM Informix Dynamic Server