CVE-2026-84326 in Chrome
Summary
by MITRE • 09/02/2026
Uninitialized resource in V8 in Google Chrome prior to 152.0.7977.75 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 09/02/2026
The vulnerability identified as an uninitialized resource issue within the V8 JavaScript engine of Google Chrome prior to version 152.0.7977.75 represents a critical memory safety flaw that undermines the browser's sandboxing mechanisms. This specific defect arises when the runtime environment fails to properly initialize certain data structures or variables before they are accessed during script execution. In complex web applications, V8 frequently allocates and manipulates various internal objects to handle dynamic content rendering and JavaScript processing. When these resources remain in an undefined state due to missing initialization routines, subsequent operations may read from or write to arbitrary memory locations rather than the intended buffers. This lack of proper setup creates a window for exploitation where malicious actors can manipulate program flow by leveraging stale or garbage data that was never cleared or set to safe defaults.
From a technical perspective, this flaw aligns with CWE-457, which describes the use of an uninitialized variable. The severity is classified as high because it directly impacts the integrity and confidentiality of user systems through remote code execution capabilities. Attackers can craft specific HTML pages containing malicious JavaScript that triggers this uninitialized state during parsing or compilation phases within V8. By carefully controlling input data, a threat actor can cause the engine to interpret memory contents in unintended ways, potentially leading to arbitrary read/write primitives. These primitives are essential for bypassing modern browser security features such as sandbox isolation and control flow integrity protections. Once these boundaries are breached, the attacker gains the ability to execute code with the privileges of the user running the browser, effectively compromising the entire system under the guise of normal web browsing activity.
The operational impact of this vulnerability is severe, particularly given its potential for remote exploitation via a crafted HTML page. Users visiting compromised or maliciously designed websites could inadvertently trigger the exploit without any additional interaction beyond loading the page. This aligns with ATT&CK technique T1059, specifically JavaScript execution, which describes how attackers use scripting languages to perform actions on local systems. The ability to execute arbitrary code inside the sandbox means that sensitive data such as cookies, session tokens, and personal information stored in browser memory can be exfiltrated. Furthermore, this initial foothold often serves as a vector for further lateral movement within an organization if the compromised machine is part of a larger network infrastructure. The lack of user interaction required makes this vulnerability particularly dangerous in phishing campaigns or drive-by download attacks where immediate exploitation is desired before any security warnings are noticed by the end-user.
Mitigation strategies primarily involve updating to Google Chrome version 152.0.7977.75 or later, which includes patches that ensure all resources within V8 are correctly initialized prior to use. Security administrators should enforce automatic update policies across all endpoints to minimize exposure windows. Additionally, organizations can implement application whitelisting and restrict the execution of unsigned scripts in high-security environments to reduce the attack surface. Network-level controls such as web filtering proxies can also be configured to block access to known malicious domains hosting exploit kits that target this specific vulnerability. Regular security audits and penetration testing focusing on browser-based attacks are recommended to identify similar memory safety issues before they can be leveraged by adversaries in the wild.