Description

Improper resource exposure in CacheStorage in Google Chrome prior to 152.0.7977.82 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-09-03T20:17:27.163Z",
  "pubdate": "2026-09-03T20:17:27.163Z",
  "executiveSummary": "A high-severity vulnerability exists within the CacheStorage API component of Google Chrome prior to version 152.0.7977.82. The flaw is categorized as an improper resource exposure, which facilitates an escape from the renderer sandbox.\nThis vulnerability allows a remote, unauthenticated attacker to execute arbitrary code within the context of the sandbox. By leveraging a crafted HTML page, an attacker can manipulate resource handling mechanisms to gain unauthorized control.\nThe risk implication is significant, as sandbox escapes undermine the core security architecture of the Chromium browser, potentially leading to unauthorized data access, cross-origin policy violations, or further exploitation of the underlying operating system.\nNo user interaction beyond navigating to a malicious web page is strictly required, making this a potent vector for drive-by download attacks. Organizations utilizing affected versions of Google Chrome are at risk of remote code execution (RCE) scenarios initiated through standard web browsing activities.\nUsers and administrators must prioritize updating to version 152.0.7977.82 or later to eliminate the exposure and restore the integrity of the browser's security boundary.",
  "technicalDetails": "The vulnerability resides within the CacheStorage implementation in the Chromium browser engine, specifically concerning how the renderer processes and exposes cached resources to web applications. CacheStorage is a service worker-associated API designed to store and retrieve network requests and responses.\nThe root cause involves a failure in the proper validation or sanitization of resources managed by the CacheStorage interface. An attacker can exploit this by crafting a malicious HTML page that initiates specific, malformed interactions with the CacheStorage API. When the renderer process attempts to load or serve a compromised resource, the improper exposure allows the attacker to influence the browser's internal logic.\nThe exploitation flow begins when a victim navigates to an attacker-controlled website. The malicious page executes JavaScript designed to manipulate the CacheStorage mechanism. Due to the lack of sufficient checks, the attacker can force the renderer process to perform operations that circumvent the sandbox isolation constraints.\nBy triggering this memory-level or state-level corruption, the attacker successfully executes arbitrary code within the renderer sandbox. While the code executes within the sandbox, the escape serves as a critical first stage in a multi-stage exploit chain, providing the attacker with a stable environment to further probe the browser's process memory or exploit additional secondary vulnerabilities in the browser process or the underlying OS kernel.\nThe vulnerability does not require prior authentication or elevated privileges. It is accessible via standard network exposure through any web content that can trigger standard API calls. The payload behavior is characterized by the injection of unauthorized logic into the browser's execution stream, which effectively bypasses the renderer's restrictive environment.\nPost-exploitation, the attacker gains the ability to execute instructions as the browser process, which may lead to persistence, data exfiltration, or the circumvention of Same-Origin Policy (SOP) protections. Because CacheStorage operates asynchronously, the exploit execution may involve race conditions or specific timing windows to maximize success in bypassing security mitigations.\nThis vulnerability highlights a critical failure in the boundary between the web-facing content and the browser's internal storage management logic, necessitating rigorous updates to the affected version of the Chromium codebase."
}