CVE-2026-1527
Description
A flaw was found in undici, a Node.js HTTP/1.1 client. This vulnerability allows a remote attacker to inject malicious data into HTTP headers or prematurely end HTTP requests by sending specially crafted input to the upgrade option of client.request(). This is possible because undici does not properly validate input for invalid header characters, which could lead to unauthorized information disclosure or bypassing of security controls.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | N/A | 4.6 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | Low |
| User Interaction | Required | N/A | Required |
| Scope | Changed | N/A | Unchanged |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | Low | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L
cve.org: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data
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