CVE-2026-118349 in Chrome
Summary
by MITRE • 10/28/2026
Memory corruption in Payments in Google Chrome prior to 156.0.8078.73 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 10/28/2026
The vulnerability identified as a memory corruption flaw within the payment handling subsystem of Google Chrome prior to version 156.0.8078.73 represents a critical breach in browser security architecture. This specific defect resides in the component responsible for processing digital transactions and managing payment-related data structures, which are inherently complex due to their interaction with external financial APIs and sensitive user credentials. The severity of this issue is classified as high by Chromium security standards because it directly compromises the integrity of the sandboxed environment that isolates web content from the underlying operating system. By exploiting a memory corruption error, an attacker can bypass these isolation mechanisms, effectively elevating privileges within the browser process to achieve arbitrary code execution with the context and permissions granted to the Chrome application itself.
The technical nature of this vulnerability involves improper handling of memory allocation or deallocation routines during the parsing or processing of crafted HTML content containing malicious payment-related scripts or embedded objects. Memory corruption vulnerabilities typically manifest as buffer overflows, use-after-free conditions, or heap overflow errors where the browser fails to validate input boundaries correctly. In this specific instance, a remote attacker could construct an HTML page that triggers these flawed memory operations when rendered by the vulnerable version of Chrome. The crafted payload likely manipulates internal data structures associated with payment processing, causing the application to write beyond allocated buffer limits or access freed memory regions. This manipulation allows for the overwriting of critical control flow data such as return addresses or function pointers, which can then be hijacked to redirect execution to attacker-controlled shellcode embedded within the malicious page.
The operational impact of this vulnerability is severe due to its remote exploitability and potential for arbitrary code execution. Since the attack vector involves a crafted HTML page, it requires no user interaction beyond visiting a compromised or specially designed website, making it suitable for drive-by download attacks. Once executed inside the sandbox, the malicious code gains access to browser-specific resources including cookies, session tokens, saved passwords, and browsing history. Although Chrome employs multiple layers of defense such as site isolation and strict origin policies, successful exploitation of this memory corruption flaw allows an attacker to escape these protections partially or fully depending on the specific nature of the heap spray or control flow hijack technique employed. This can lead to full system compromise if further privilege escalation techniques are applied post-exploitation within the browser process context.
Mitigation strategies primarily involve immediate software updates and defensive configuration adjustments. Users must upgrade Google Chrome to version 156.0.8078.73 or later, where the underlying memory management routines in the payment subsystem have been patched to enforce strict bounds checking and prevent invalid memory access patterns. For organizations managing large fleets of devices, automated patch deployment systems should be utilized to ensure rapid remediation across all endpoints. Additionally, enabling Chrome’s sandboxing features fully and restricting script execution from untrusted origins can reduce the attack surface. Security teams should also monitor for indicators of compromise related to unusual network connections or process behavior originating from browser processes, as these may signal active exploitation attempts targeting this vulnerability before patches are applied industry-wide.
This incident aligns with common weakness enumeration standards such as CWE-120 Buffer Copy without Checking Size of Input and CWE-416 Use After Free, which describe the fundamental memory safety failures that lead to code execution vulnerabilities in modern software applications. From a threat intelligence perspective, this exploitation technique maps to MITRE ATT&CK techniques including T1203 Exploitation for Client Execution and potentially T1059 Command and Scripting Interpreter if the executed payload involves scripting languages like JavaScript or PowerShell within the browser context. Understanding these mappings helps security professionals anticipate similar attack patterns in other applications that handle complex user inputs with insufficient validation, reinforcing the importance of rigorous memory safety practices and continuous vulnerability management programs to mitigate risks associated with high-severity remote code execution flaws.