CVE-2026-113239 in Chrome
Summary
by MITRE • 10/21/2026
Range error in SiteIsolation in Google Chrome on on Android prior to 156.0.8078.47 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 10/21/2026
The vulnerability identified as a range error within the SiteIsolation component of Google Chrome on Android represents a significant breach in browser-based isolation mechanisms, allowing for potential remote code execution under specific conditions. This flaw exists prior to version 156.0.8078.47 and is classified with a medium severity rating by Chromium security teams, indicating that while the exploitability may require certain prerequisites or user interaction, the impact on system integrity is substantial. The core of this issue lies in how Chrome handles memory boundaries when processing web content across different sites, a critical function for maintaining sandboxing effectiveness against cross-site attacks.
SiteIsolation is a fundamental security feature designed to prevent attackers from stealing sensitive data such as cookies or session tokens by ensuring that processes are isolated based on site origin rather than just tab identity. When this mechanism fails due to improper range checking during the processing of crafted HTML pages, it creates an opportunity for memory corruption. Specifically, the range error suggests a failure in validating array indices or buffer sizes, which can lead to out-of-bounds reads or writes. In the context of Chrome's multi-process architecture, such errors within privileged components or those handling cross-origin data can allow malicious scripts embedded in a crafted webpage to escape the restrictive sandbox environment that normally limits their capabilities.
The operational impact of this vulnerability is severe for end-users who visit compromised or maliciously constructed websites. An attacker could craft an HTML page containing specific JavaScript and other web technologies designed to trigger the range error during rendering or script execution. If successful, this allows arbitrary code execution within the context of the browser process associated with that site. This effectively bypasses the sandbox protections intended to contain malware and limit the damage a compromised webpage can inflict on the underlying operating system. The attacker gains the ability to execute commands, potentially leading to data exfiltration, installation of further malicious payloads, or complete compromise of the Android device depending on the privileges held by the browser process at the time of exploitation.
From a classification perspective, this vulnerability aligns with CWE-120 Buffer Copy without Checking Size of Input and CWE-787 Out-of-bounds Write, which are common root causes for memory corruption vulnerabilities in C++ based applications like Chrome. In terms of adversary tactics, this falls under the MITRE ATT&CK technique T1059 Command and Scripting Interpreter, specifically through JavaScript execution within a browser context, followed by potential privilege escalation if the sandbox is fully breached. The exploitation vector is remote via network (T1189 Drive-by Compromise), requiring only that the victim visits the crafted URL, making it particularly dangerous in phishing campaigns or on compromised advertising networks.
Mitigation strategies primarily involve immediate software updates to ensure users are running version 156.0.8078.47 or later of Google Chrome for Android. Since this is a client-side vulnerability, patching remains the most effective defense against exploitation attempts that rely on specific memory layout conditions which may change with each update. Additionally, organizations should enforce strict content security policies and utilize browser hardening techniques to limit script execution capabilities where possible. Users are advised to keep their devices updated automatically and avoid visiting untrusted websites until patches have been applied across the user base. Security monitoring tools that detect anomalous memory access patterns or unusual process behavior in Chrome can also provide secondary layers of defense against exploitation attempts targeting this specific flaw.