CVE-2026-15769 in Chrome
Summary
by MITRE • 07/15/2026
Insufficient validation of untrusted input in Linux Toolkit Theming in Google Chrome on Linux prior to 150.0.7871.125 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 • 07/15/2026
This vulnerability represents a critical sandbox escape vector in Google Chrome's Linux implementation that stems from inadequate input validation within the Linux Toolkit Theming component. The flaw exists specifically in versions prior to 150.0.7871.125 and allows a remote attacker who has already compromised the renderer process to potentially break out of Chrome's sandbox protection mechanisms. The vulnerability is classified as high severity by Chromium security standards, indicating its potential for significant system compromise.
The technical exploitation occurs through a crafted HTML page that leverages insufficient validation of untrusted input in the Linux Toolkit Theming functionality. This component handles theming elements for Chrome's user interface on Linux systems, and the improper input sanitization creates an attack surface where malicious code can manipulate the application's behavior beyond its intended boundaries. The vulnerability specifically targets the renderer process compromise scenario, where an attacker has already gained execution privileges within Chrome's isolated rendering environment but seeks to extend their control beyond the sandbox.
Operating impact of this vulnerability extends beyond simple privilege escalation as it fundamentally undermines Chrome's security architecture on Linux platforms. When successfully exploited, the sandbox escape allows attackers to bypass Chrome's multi-process security model that isolates different parts of the browser from each other and from the underlying operating system. This enables potential access to system resources, file operations, and communication with other processes that should normally be restricted within the sandboxed environment. The vulnerability essentially creates a pathway for attackers to move laterally from the compromised renderer process into deeper system access.
Mitigation strategies should focus on immediate remediation through Chrome version updates to 150.0.7871.125 or later, which contain fixes addressing the input validation deficiencies in the Linux Toolkit Theming component. Organizations should also implement additional security measures including network monitoring for suspicious HTML content delivery, browser hardening configurations that limit unnecessary permissions, and regular security audits of web applications that may be exposed to this vulnerability. From a compliance perspective, this vulnerability aligns with CWE-20 standards related to improper input validation and relates to ATT&CK technique T1059 for command and scripting interpreter execution. The fix addresses the core issue by implementing proper input sanitization mechanisms that validate all untrusted data before processing within the theming subsystem.
The vulnerability demonstrates the critical importance of maintaining comprehensive input validation across all application components, particularly those handling user-facing interface elements that may be exposed to remote content. It highlights the need for robust security testing practices that include threat modeling for sandboxed environments and proper boundary validation between different privilege levels within browser architectures. This particular flaw serves as a reminder that even seemingly benign UI components can represent significant security risks when they fail to properly validate input from untrusted sources, creating potential escape routes for attackers who have already achieved initial compromise within the browser's security model.