CVE-2026-118338 in Chrome
Summary
by MITRE • 10/28/2026
Use after free in Animation in Google Chrome prior to 156.0.8078.73 allowed a remote attacker to potentially execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 10/28/2026
The vulnerability identified as a use-after-free error within the Animation subsystem of Google Chrome prior to version 156.0.8078.73 represents a critical memory safety flaw that undermines the browser's sandboxing mechanisms. This specific class of vulnerabilities arises when an application continues to reference a memory block after it has been freed, leading to undefined behavior that can be exploited by malicious actors. In this instance, the defect resides in how Chrome handles animation objects during their lifecycle management, specifically failing to properly nullify pointers or update references before deallocating the associated memory resources. This oversight creates a window of opportunity where an attacker who controls the input data can manipulate the state of these dangling pointers to achieve unintended side effects within the browser process.
From a technical perspective, use-after-free vulnerabilities are particularly dangerous because they allow for arbitrary read and write operations in memory space that should be isolated from user-controlled content. When the compromised animation object is accessed after its underlying memory has been returned to the heap allocator, an attacker can craft specific HTML pages containing malicious JavaScript or CSS animations designed to trigger this condition. By carefully controlling the timing of deallocation and subsequent access, the attacker can overwrite adjacent objects in memory with controlled data structures. This capability effectively bypasses standard security boundaries, allowing for code execution within the context of the browser process itself rather than just rendering content on a webpage.
The operational impact of this vulnerability is severe due to its potential for remote code execution via a crafted HTML page. An attacker does not need physical access or prior authentication; instead, they can distribute malicious links through phishing campaigns, compromised websites, or other social engineering vectors that entice users into visiting the exploit payload. Once loaded in an affected version of Chrome, the vulnerability allows the execution of arbitrary commands with the privileges of the user running the browser. This compromises not only the confidentiality and integrity of browsing data but also potentially leads to full system compromise if further exploitation steps are chained together to escape the sandbox environment entirely.
Industry standards classify this flaw under CWE-416, which defines use after free as a condition where software uses memory after it has been freed, often leading to crashes or arbitrary code execution. Furthermore, in terms of tactical mapping within the MITRE ATT&CK framework, this vulnerability facilitates initial access and privilege escalation techniques commonly associated with browser exploitation chains. The medium severity rating assigned by Chromium reflects the complexity required to reliably exploit the flaw compared to more straightforward memory corruption issues, yet it remains a significant risk given the widespread adoption of Chrome as a primary web browsing platform.
Mitigation strategies primarily involve immediate patching to version 156.0.8078.73 or later, where Google has addressed the lifecycle management errors within the animation engine. Security teams should ensure that automatic updates are enabled for all endpoints running affected versions of Chrome to minimize exposure windows. Additionally, organizations can employ application whitelisting and strict content security policies to restrict the execution of untrusted scripts on internal networks. Monitoring browser telemetry for unusual memory allocation patterns or crashes related to rendering processes may also help in detecting attempted exploitation activities before they result in successful compromise.