CVE-2026-106231 in Chrome
Summary
by MITRE • 10/06/2026
Uninitialized resource in Dawn in Google Chrome on on Mac prior to 155.0.8059.39 allowed a remote attacker to read memory outside the sandbox via a crafted HTML page. (Chromium security severity: High)
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 10/07/2026
The vulnerability identified as an uninitialized resource issue within the Dawn graphics engine of Google Chrome on macOS represents a significant security flaw that undermines the browser's core isolation mechanisms. This defect, present in versions prior to 155.0.8059.39, stems from improper initialization of memory or state variables associated with WebGL context operations managed by Dawn. When an attacker crafts a malicious HTML page containing specific JavaScript code designed to trigger complex graphics rendering pipelines, the browser fails to properly initialize certain internal data structures before they are accessed. This oversight results in the reading of uninitialized memory regions that may contain sensitive information previously held by other processes or objects within the same address space. The severity is classified as high because it directly facilitates a sandbox escape scenario, allowing code execution outside the restricted environment intended for web content.
From a technical perspective, Dawn serves as Chrome's implementation layer for WebGL and WebGPU on macOS, translating browser API calls into native graphics commands via Metal or OpenGL ES. When handling crafted input that manipulates shader programs, buffer bindings, or texture uploads, the engine may proceed with operations before ensuring all required state variables are zeroed out or set to safe defaults. Consequently, when these uninitialized pointers or values are dereferenced during rendering or memory management tasks, they can point to arbitrary locations in process memory. This behavior aligns closely with CWE-457, which describes the use of an uninitialized variable, and often leads to information disclosure vulnerabilities where attackers can exfiltrate data from adjacent memory regions that should remain inaccessible due to browser sandboxing policies.
The operational impact of this vulnerability is severe for users relying on Chrome for browsing untrusted websites or executing web-based applications. A remote attacker hosting a malicious webpage could exploit this flaw by tricking a victim into visiting the site, thereby triggering the uninitialized read condition without any user interaction beyond loading the page. Once exploited, the attacker gains the ability to read memory outside the sandbox boundary, potentially accessing cookies, session tokens, passwords stored in autofill fields, or other sensitive data belonging to the current browsing context. This breach of isolation compromises the confidentiality and integrity guarantees provided by Chrome's multi-process architecture, effectively neutralizing one of the primary defenses against web-based attacks such as cross-site scripting follow-ups or drive-by downloads that rely on sandbox escapes for privilege escalation.
Mitigation strategies primarily involve updating Google Chrome to version 155.0.8059.39 or later, where this initialization logic has been corrected to ensure all relevant resources are properly set before use. Organizations should enforce automatic update policies across all endpoints running macOS to minimize the window of exposure. Additionally, security teams can implement network-level controls such as web filtering proxies that block access to known malicious domains hosting exploit kits targeting browser vulnerabilities. For environments where immediate patching is not feasible, enabling Chrome's Site Isolation feature and restricting WebGL permissions through enterprise policy configurations can reduce the attack surface by limiting the capabilities available to untrusted origins. Monitoring for anomalous memory access patterns or unusual GPU utilization spikes may also serve as an indicator of attempted exploitation in real-time threat detection systems aligned with MITRE ATT&CK techniques related to sandbox evasion and data exfiltration from local applications.