CVE-2026-113309 in Chrome
Summary
by MITRE • 10/21/2026
Out of bounds read in Media in Google Chrome prior to 156.0.8078.47 allowed a remote attacker to read memory inside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 10/21/2026
The vulnerability identified as an out-of-bounds read within the Media component of Google Chrome prior to version 156.0.8078.47 represents a critical failure in memory safety enforcement during media processing operations. This flaw allows for unauthorized access to system memory that resides outside the intended boundaries of allocated buffers, potentially exposing sensitive data or internal application states to external actors. The severity is classified as High by Chromium security standards due to the potential for information disclosure and the possibility of leveraging this read primitive to facilitate further exploitation within the browser's sandboxed environment.
The technical root cause lies in improper boundary checks during the parsing or rendering of media content, such as video streams or audio files embedded via HTML tags. When a crafted HTML page containing maliciously constructed media elements is loaded by an affected version of Chrome, the Media component fails to validate that memory access requests remain within the allocated buffer limits. This lack of validation permits the browser engine to read from adjacent memory locations that were not intended for public consumption. The attacker crafts specific input parameters or file structures that trigger this erroneous behavior, causing the application to retrieve data from arbitrary memory addresses rather than stopping at the end of the valid data segment.
From an operational perspective, this vulnerability enables a remote attacker to perform information disclosure attacks against users who visit maliciously hosted web pages. By carefully analyzing the returned out-of-bounds data, an attacker can potentially leak stack pointers, heap metadata, or other sensitive information that aids in bypassing security mitigations such as Address Space Layout Randomization (ASLR). Although Chrome employs a multi-process architecture with sandboxing to limit the impact of vulnerabilities, successful exploitation of this read primitive can provide the necessary context for more severe attacks, including arbitrary code execution if combined with additional primitives or specific browser states. The attack vector is remote and requires user interaction in the form of visiting a specially crafted webpage, making it suitable for phishing campaigns or drive-by download scenarios where social engineering tactics are employed to lure victims into accessing malicious content.
This vulnerability aligns with Common Weakness Enumeration (CWE) category CWE-125, which describes Out-of-bounds Read vulnerabilities resulting from insufficient validation of array indices or buffer boundaries. In the context of the MITRE ATT&CK framework, this flaw facilitates reconnaissance and privilege escalation techniques by allowing attackers to gather information about the target environment without triggering immediate detection mechanisms associated with more aggressive memory corruption exploits. The ability to read arbitrary memory is a foundational step in many advanced persistent threat (APT) strategies, as it provides insight into how security controls are configured on the victim's system.
Mitigation for this vulnerability primarily involves updating Google Chrome to version 156.0.8078.47 or later, where the boundary checks within the Media component have been corrected to prevent access beyond allocated memory regions. Organizations should enforce automated update policies to ensure all endpoints are running patched versions of the browser. Additionally, users can reduce their exposure by disabling JavaScript execution on untrusted sites using content security policies or browser extensions that restrict media playback from unknown origins. Security teams should also monitor for indicators of compromise related to unusual network traffic patterns originating from browsers attempting to exfiltrate data through covert channels established via memory leaks, although such detection is challenging without endpoint protection solutions capable of deep packet inspection and behavioral analysis.