CVE-2026-119270 in Chrome
Summary
by MITRE • 10/30/2026
Improper input validation in CacheStorage in Google Chrome prior to 156.0.8078.79 allowed a remote attacker to potentially execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 10/30/2026
The vulnerability identified as an improper input validation flaw within the CacheStorage component of Google Chrome prior to version 156.0.8078.79 represents a significant breach in browser-side data handling integrity. This specific weakness allows for potential arbitrary code execution inside the sandbox, which is a critical security boundary designed to isolate web content from the underlying operating system and user files. The root cause lies in how the CacheStorage API processes incoming data structures without sufficiently verifying their format or boundaries before internal operations are performed. When a remote attacker crafts an HTML page that triggers this specific code path with malformed or specially constructed input, it can lead to memory corruption or logic errors that bypass standard security checks. This type of flaw is commonly categorized under CWE-20 Improper Input Validation and often relates to CWE-119 Memory Buffer Corruption if the validation failure results in out-of-bounds writes or reads within the browser's memory space.
The operational impact of this vulnerability is severe due to its remote exploitability via a simple web page visit, which aligns with ATT&CK technique T1059 Command and Scripting Interpreter through browser-based exploitation vectors. An attacker does not need physical access or user interaction beyond visiting a malicious site, making it suitable for drive-by download attacks or targeted phishing campaigns where the victim is tricked into loading the crafted page. Once executed inside the sandbox, the arbitrary code execution could allow the attacker to perform actions such as stealing sensitive cookies and session tokens, keylogging, or further pivoting if the sandbox escape succeeds. Although Chrome’s sandboxing architecture provides a robust defense-in-depth strategy that limits the immediate impact of renderer process compromises, any successful exploitation within this environment still poses a high risk to user privacy and data integrity. The Chromium security severity rating of High reflects the likelihood of exploitability and the potential for significant harm if the isolation mechanisms are bypassed or if the vulnerability is chained with other flaws to achieve full sandbox escape.
Mitigation strategies primarily involve immediate patching by updating Google Chrome to version 156.0.8078.79 or later, which contains the necessary code fixes to enforce stricter input validation within CacheStorage operations. For organizations managing large fleets of devices, deploying automated update policies ensures that this vulnerability is addressed across all endpoints without relying on individual user action. Additionally, security teams should monitor for indicators of compromise associated with drive-by exploitation attempts and consider implementing content security policies or browser hardening configurations to restrict the execution of untrusted scripts where possible. While technical controls are essential, user awareness training remains a critical layer in defense against social engineering tactics that lead victims to interact with malicious web pages containing such crafted inputs. Regular vulnerability scanning and penetration testing can also help identify similar implementation flaws in custom applications or extensions that rely on browser APIs for data storage.