CVE-2026-53669 in react-router
Summary
by MITRE • 07/28/2026
React Router is a router for React. Versions 6.0.0 through 7.17.0 are vulnerable to Open Redirtect through use of backslashes in and useNavigate. This issue is a follow up to CVE-2025-68470 and has been fixed in version 7.18.0.
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Analysis
by VulDB Data Team • 07/28/2026
The vulnerability in React Router affects versions 6.0.0 through 7.17.0 and represents a critical open redirect flaw that can be exploited through improper handling of backslashes in navigation parameters. This security weakness specifically impacts the useNavigate hook and route configuration components where backslash characters are processed without adequate sanitization or validation. The vulnerability allows attackers to manipulate navigation flows by injecting backslash sequences that can bypass intended security controls and redirect users to malicious external destinations.
The technical implementation flaw stems from how React Router processes URL paths containing backslashes during navigation operations. When the useNavigate hook encounters route parameters or path segments with backslash characters, the routing library fails to properly normalize or validate these inputs before executing redirects. This processing gap creates an opportunity for attackers to craft malicious URLs that exploit the backslash handling mechanism, potentially leading to unauthorized redirections to attacker-controlled domains.
This vulnerability directly relates to CWE-601 which defines open redirect vulnerabilities as security flaws that allow web applications to redirect users to external websites without proper validation of the destination. The issue falls under the broader category of insecure direct object references and represents a significant risk to user safety and application integrity. The exploitation of this flaw can lead to phishing attacks, credential theft, or other malicious activities where unsuspecting users are redirected to compromised websites that appear legitimate within the context of the original application.
The operational impact of this vulnerability extends beyond simple redirection scenarios as it undermines fundamental security assumptions in web applications built with React Router. Attackers can leverage this flaw to create convincing phishing pages that mimic legitimate application interfaces, potentially capturing user credentials or sensitive information through social engineering combined with the automatic redirection capability. The vulnerability affects both server-side and client-side rendering environments where React Router components are utilized, making it particularly dangerous across different deployment scenarios.
Organizations using affected versions of React Router should immediately upgrade to version 7.18.0 or later to address this security gap. The fix implemented in version 7.18.0 includes enhanced input validation for navigation parameters and proper handling of backslash sequences in route processing. Additionally, developers should review all navigation logic within their applications to ensure that user-supplied inputs are properly sanitized before being passed to navigation functions. Security teams should monitor for suspicious redirect patterns and implement network-level controls to detect and block unauthorized redirection attempts.
The vulnerability also aligns with ATT&CK technique T1566 which covers social engineering tactics including phishing attacks, where the open redirect capability can be weaponized to create convincing fake login pages or malicious landing sites. This makes the vulnerability particularly dangerous in enterprise environments where users may trust legitimate application interfaces and are less likely to scrutinize redirects that appear to originate from trusted sources. The security implications extend to compliance requirements for applications handling sensitive data, as this flaw could potentially lead to violations of data protection regulations if user information is compromised through unauthorized redirections.
Security monitoring should include detection of unusual navigation patterns involving backslash characters in URL parameters and tracking of redirect events to identify potential exploitation attempts. Organizations should also consider implementing additional security layers such as Content Security Policy headers and referer validation mechanisms to provide defense-in-depth against this class of vulnerability. The fix addresses the core issue by ensuring that all backslash sequences are properly normalized during navigation processing, preventing attackers from leveraging these characters to manipulate redirect behavior.
This vulnerability serves as a reminder of the importance of input validation in web applications and highlights how seemingly minor implementation details can create significant security risks. The React Router team's response demonstrates proper vulnerability management through timely patching and clear communication about the security implications. Organizations should maintain updated threat intelligence on similar vulnerabilities in their component libraries and ensure regular security assessments of their application frameworks to prevent exploitation of similar flaws that may not yet be publicly disclosed but could pose equivalent risks to their systems.