CVE-2026-93376 in Chrome
Summary
by MITRE • 09/17/2026
Out of bounds read in DataTransfer in Google Chrome prior to 153.0.8010.52 allowed a local attacker leveraging social engineering to read memory outside the sandbox via a local program. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 09/17/2026
The vulnerability identified as an out-of-bounds read within the DataTransfer object in Google Chrome prior to version 153.0.8010.52 represents a significant breach of memory safety principles, specifically categorized under CWE-125 which denotes Out-of-Bounds Read. This flaw resides within the browser's handling of data transfer operations, typically associated with drag-and-drop functionality or clipboard interactions where content is moved between different contexts or applications. The core technical issue arises from insufficient validation checks when accessing array indices or memory buffers during these transfers. When a specific sequence of events triggers this code path, the application fails to verify that the requested index falls within the allocated bounds of the underlying data structure. Consequently, instead of throwing an exception or returning null as expected in secure implementations, the browser proceeds to read from adjacent memory locations that were not intended for access by the current operation.
The operational impact of this vulnerability is particularly severe due to its potential to bypass Chrome's sandboxing mechanisms. Modern browsers employ a multi-process architecture where renderer processes are heavily restricted and isolated from sensitive system resources through sandboxes designed to limit the damage caused by exploits. However, an out-of-bounds read can serve as a primitive for information disclosure or even code execution if combined with other techniques such as heap spraying or type confusion attacks. In this specific instance, the vulnerability allows a local attacker who has successfully leveraged social engineering tactics to trick a user into executing a malicious local program. This program interacts with the browser in a way that triggers the flawed DataTransfer logic, enabling the reading of memory contents outside the sandboxed environment. The ability to read arbitrary memory can lead to the leakage of sensitive information such as session cookies, authentication tokens, or cryptographic keys stored within the browser's process space.
From an attacker perspective, this vulnerability aligns with ATT&CK techniques related to Initial Access and Defense Evasion. Specifically, it relates to T1566 which covers Phishing, where social engineering is used to deliver the initial payload, and potentially T1074 or similar data staging mechanisms if the exfiltrated memory content is processed further. The medium severity rating assigned by Chromium reflects that while exploitation requires user interaction and a local foothold via social engineering, the potential for privilege escalation through sandbox escape makes it dangerous in targeted attacks. An attacker does not need to exploit a remote vector but rather relies on convincing a victim to run a locally hosted malicious script or application that interacts with Chrome's internal APIs incorrectly.
Mitigation strategies primarily involve updating Google Chrome to version 153.0.8010.52 or later, where the bounds checking logic for DataTransfer operations has been corrected to prevent access beyond allocated memory regions. For organizations managing large fleets of endpoints, automated patch management systems should be configured to prioritize this update given its potential impact on data confidentiality and integrity. Additionally, users should remain vigilant against social engineering attempts that encourage running unknown local programs or scripts, as these are the primary vectors for triggering such vulnerabilities. Security awareness training emphasizing the risks of executing untrusted code locally can significantly reduce the likelihood of successful exploitation in environments where browser-based attacks might be attempted by threat actors with limited initial access privileges.