CVE-2026-21132 in Internet
Summary
by MITRE • 10/12/2026
Improper input validation in Samsung Internet prior to version 30.0.5.24 allows remote attackers to inject arbitrary script. User interaction is required for triggering this vulnerability.
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Analysis
by VulDB Data Team • 10/12/2026
The identified vulnerability represents a classic cross-site scripting (XSS) flaw within the Samsung Internet browser, specifically affecting versions preceding 30.0.5.24. This security defect stems from improper input validation mechanisms embedded in how the browser processes and renders web content. When a user navigates to a maliciously crafted webpage or interacts with a compromised site, the application fails to adequately sanitize or encode special characters within user-supplied data before it is processed by the rendering engine. Consequently, this oversight allows an attacker to inject arbitrary script code into the context of the victim's session. The core technical failure lies in the browser’s inability to distinguish between legitimate content and executable malicious payloads during the parsing phase, thereby violating fundamental principles of secure coding regarding input handling and output encoding.
From a classification perspective, this vulnerability aligns with CWE-79, which denotes Improper Neutralization of Input During Web Page Generation commonly known as Cross-site Scripting. The specific nature of the flaw suggests that the browser did not properly validate inputs against expected formats or failed to apply appropriate escaping mechanisms for characters such as angle brackets, quotes, and ampersands. This lack of rigorous validation permits the injection of JavaScript code that executes within the security context of the visited website. Because the vulnerability resides in a web browser rather than a specific server-side application, it exploits the trust relationship between the user and the domain they are visiting, allowing scripts to access cookies, local storage, or other sensitive data associated with that origin.
The operational impact of this vulnerability is significant due to its potential for privilege escalation within the scope of the victim's browsing session. Although user interaction is required to trigger the exploit—typically by clicking a link or loading a specific page—the consequences can be severe if successful. An attacker could steal authentication tokens, hijack active sessions, perform actions on behalf of the user without their consent, or redirect the user to phishing sites designed to capture further credentials. In enterprise environments where Samsung Internet may be used for accessing internal web applications, this vulnerability poses a risk to corporate data integrity and confidentiality. The requirement for user interaction mitigates some automated attack vectors but does not eliminate the threat posed by social engineering tactics that trick users into visiting malicious URLs.
To mitigate this risk, organizations and individual users must ensure that Samsung Internet is updated to version 30.0.5.24 or later, where these input validation flaws have been addressed through enhanced sanitization routines and stricter parsing rules. Security administrators should enforce automatic update policies for all devices running the affected browser versions to minimize exposure windows. Additionally, implementing Content Security Policy (CSP) headers on web applications accessed via Samsung Internet can provide an additional layer of defense by restricting the sources from which scripts are allowed to execute. While CSP does not fix the underlying vulnerability in the browser itself, it significantly reduces the impact of any successful injection attempts by preventing unauthorized script execution. Regular security awareness training for users regarding suspicious links and untrusted websites also serves as a critical human firewall against exploitation of this type of client-side vulnerability.