CVE-2026-48615 in Node.js
Summary
by MITRE • 06/26/2026
A flaw in Node.js proxy tunnel error handling could expose proxy credentials in `ERR_PROXY_TUNNEL` error messages.
When proxy credentials are embedded in the proxy URL, they may be exposed through error handling paths and captured by logs, diagnostics, or other error consumers.
This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 06/27/2026
This vulnerability represents a critical information exposure flaw in Node.js proxy tunnel error handling mechanisms that directly impacts the security posture of applications relying on proxy configurations. The issue stems from improper sanitization of proxy credentials within error messages, specifically during the ERR_PROXY_TUNNEL error handling process where authentication details become inadvertently exposed through various diagnostic pathways. When applications utilize proxy URLs containing embedded credentials such as username:password@proxyhost:port, the vulnerability allows these sensitive components to be included in error logs and diagnostic outputs, creating a direct attack vector for credential theft.
The technical implementation of this flaw occurs within Node.js core networking modules where proxy tunnel establishment failures trigger error messages that do not adequately sanitize credential information from URLs before being processed by logging systems or error consumers. This behavior violates fundamental security principles around information hiding and privilege separation, as the system inadvertently exposes authentication tokens that should remain confidential during operational failures. The vulnerability affects multiple active release lines including Node.js 22, 24, and 26, indicating a widespread impact across the current supported versions of the platform.
The operational impact of this vulnerability extends beyond simple credential exposure to encompass broader security implications for applications deployed in production environments. When proxy credentials are logged or transmitted through error handling pathways, attackers with access to system logs, monitoring tools, or diagnostic interfaces can extract authentication information that grants them unauthorized access to corporate networks, external services, and potentially sensitive data repositories. This flaw particularly affects enterprise applications that rely on authenticated proxy configurations for network access control, making it a significant concern for organizations implementing security policies around credential management.
From a cybersecurity perspective, this vulnerability aligns with CWE-209 Information Exposure Through an Error Message, which specifically addresses the risk of exposing sensitive information through error handling mechanisms. The flaw also intersects with ATT&CK technique T1566.002 Credential Access: Phishing for Information, as it enables adversaries to harvest credentials from system diagnostics without requiring traditional phishing or social engineering approaches. Organizations should consider this vulnerability as part of their broader credential exposure risk assessment and implement immediate mitigations while awaiting official patches.
The recommended mitigation strategy involves applying the latest security updates from Node.js release channels that address the proxy tunnel error handling implementation. Until patch deployment, administrators should consider implementing additional logging controls to prevent credential exposure in diagnostic outputs, such as configuring log sanitization filters or modifying application code to avoid embedding credentials in proxy URLs where possible. Security teams should also conduct comprehensive audits of existing proxy configurations and monitoring systems to identify any potential credential exposure previously occurring through this vulnerability channel.