CVE-2026-4451 in Chrome
Summary
by MITRE • 03/20/2026
Insufficient validation of untrusted input in Navigation in Google Chrome prior to 146.0.7680.153 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 03/25/2026
This vulnerability represents a critical sandbox escape flaw in Google Chrome's navigation handling mechanism that existed prior to version 146.0.7680.153. The issue stems from inadequate validation of untrusted input within the browser's navigation subsystem, creating a pathway for malicious actors who have already compromised the renderer process to potentially break out of the sandboxed environment. The vulnerability is classified as high severity by Chromium security standards, indicating the significant risk it poses to overall browser security architecture. The flaw specifically affects the way Chrome processes navigation requests from untrusted HTML content, failing to properly validate or sanitize input that could be manipulated to exploit the sandbox boundaries.
The technical exploitation of this vulnerability occurs when an attacker successfully compromises the renderer process through some initial attack vector, such as a phishing page or malicious attachment. Once inside the renderer process, the attacker can craft a specially designed HTML page that leverages the insufficient input validation to manipulate navigation behavior. This manipulation allows the attacker to execute code outside the normal sandbox boundaries, effectively escalating privileges and potentially gaining access to system resources that should remain isolated. The vulnerability essentially creates a bypass mechanism that undermines the fundamental security model of Chrome's multi-process architecture, where the renderer process is designed to be isolated from the main browser process and system resources.
From an operational impact perspective, this vulnerability represents a severe threat to user security and privacy, particularly in environments where users may be targeted by sophisticated attackers. The attack requires initial compromise of the renderer process, which is often achieved through social engineering, drive-by downloads, or exploitation of other browser vulnerabilities. However, once achieved, the sandbox escape capability allows attackers to perform actions such as reading arbitrary files from the filesystem, executing arbitrary code with system privileges, or accessing sensitive user data. This makes the vulnerability particularly dangerous in enterprise environments where users may have access to sensitive corporate data or where attackers are specifically targeting high-value targets.
The mitigation strategy for this vulnerability involves immediate upgrade to Chrome version 146.0.7680.153 or later, which includes patches addressing the input validation issues in the navigation subsystem. Organizations should also implement additional security measures such as maintaining up-to-date browser versions, deploying web application firewalls, and monitoring for suspicious navigation patterns in network traffic. Security teams should conduct regular vulnerability assessments and penetration testing to identify potential exploitation vectors, while also educating users about phishing threats and social engineering attacks that could lead to initial compromise. The fix addresses the underlying CWE-20 vulnerability pattern related to improper input validation, which is a common weakness in web applications and browsers that can lead to various security issues including privilege escalation and sandbox escapes. This vulnerability aligns with ATT&CK techniques related to privilege escalation and sandbox evasion, specifically targeting the T1059 and T1497 tactics that involve executing commands and bypassing system protections respectively.