CVE-2026-106426 in Chrome
Summary
by MITRE • 10/07/2026
Race condition in Fonts in Google Chrome prior to 155.0.8059.39 allowed a remote attacker to potentially execute arbitrary code outside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 10/07/2026
The vulnerability identified as a race condition within the font handling subsystem of Google Chrome prior to version 155.0.8059.39 represents a critical failure in synchronization mechanisms that govern memory access during concurrent operations. This flaw allows an attacker who crafts a malicious HTML page containing specially designed font resources to exploit timing discrepancies between different threads or processes within the browser engine. When the browser parses and renders these crafted fonts, it fails to properly serialize access to shared data structures associated with font rendering pipelines. This lack of atomicity creates a window where memory states can be manipulated in unintended ways, potentially leading to heap corruption or use-after-free conditions that bypass standard sandboxing protections.
From a technical perspective, the core issue lies in how Chrome manages resources related to font files during high-concurrency scenarios typical of modern web page rendering. The race condition likely occurs when one thread is modifying internal state variables while another thread reads them without adequate locking mechanisms or memory barriers. In the context of browser security architecture, such races are particularly dangerous because they can lead to arbitrary code execution outside the restricted sandbox environment that isolates renderer processes from the operating system and user data. The Chromium project has classified this issue with a High severity rating due to its potential for remote exploitation through standard web delivery mechanisms without requiring user interaction beyond visiting a malicious site or having it loaded via an iframe.
The operational impact of this vulnerability is severe, as successful exploitation could result in full compromise of the victim's system under certain conditions where sandbox escape techniques are combined with the race condition exploit chain. An attacker can leverage this flaw to execute arbitrary code on the target machine, effectively breaking out of the browser's security boundaries. This capability undermines one of the primary defenses against web-based attacks, allowing malware installation, data exfiltration, or further lateral movement within a network if the user is part of an enterprise environment. The ability to execute code outside the sandbox means that traditional endpoint protection solutions may not immediately detect the malicious activity originating from what appears to be legitimate browser processes.
Mitigation strategies primarily involve updating Google Chrome to version 155.0.8059.39 or later, where these synchronization issues have been addressed through improved locking mechanisms and stricter validation of font resource states during concurrent access. Organizations should ensure that automatic updates are enabled for all endpoints running the browser to minimize exposure windows. Additionally, security teams can implement network-level controls such as web filtering proxies to block known malicious domains hosting crafted HTML pages containing exploit code until patching is complete. Monitoring for unusual process behavior or memory allocation patterns associated with font rendering modules may also aid in detecting attempted exploitation of this vulnerability before successful compromise occurs.
This incident aligns with Common Weakness Enumeration category CWE-362, which describes concurrent execution using shared resources with improper synchronization leading to race conditions. It also relates to MITRE ATT&CK technique T1059, specifically command and script interpreters used for post-exploitation activities following initial access through web delivery attacks like CVE-based exploits in browsers. Understanding these classifications helps security professionals map the vulnerability to broader threat landscapes and prioritize remediation efforts based on industry-standard risk frameworks.