CVE-2026-95338 in Chrome
Summary
by MITRE • 09/29/2026
Use after free in PDFium in Google Chrome prior to 154.0.8037.57 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted PDF file. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 09/29/2026
The vulnerability identified as a use-after-free flaw within the PDFium component of Google Chrome represents a critical memory corruption issue that was addressed in version 154.0.8037.57 and later releases. This specific class of vulnerabilities arises when software continues to use a pointer after it has been freed, leading to undefined behavior that can be exploited by malicious actors. In the context of PDFium, which is responsible for rendering Portable Document Format files within the Chromium browser engine, this flaw allowed an attacker who crafted a specially designed PDF file to trigger the premature deallocation of memory while references to that memory were still active in the application's execution flow.
From a technical perspective, the exploitation mechanism relies on manipulating the lifecycle management of objects within the PDF rendering pipeline. When a user opens or interacts with a maliciously constructed PDF document, specific parsing routines may free internal data structures prematurely. Subsequent operations that attempt to access these freed memory regions can result in arbitrary code execution if the attacker has successfully controlled the contents of the reclaimed memory space through heap spraying techniques or other memory corruption strategies. This scenario is particularly dangerous because it bypasses standard safety checks and allows for direct manipulation of the program's control flow, potentially leading to full system compromise depending on the privileges under which the browser process operates.
The operational impact of this vulnerability is severe due to its remote exploitability via a crafted PDF file. An attacker does not need physical access or user interaction beyond opening the malicious document in an affected version of Chrome prior to the specified patch level. The severity rating of High by the Chromium security team reflects the potential for arbitrary code execution within the browser's sandbox environment. While modern browsers employ robust sandboxing mechanisms designed to limit the damage caused by such exploits, a successful use-after-free attack can potentially escape these restrictions or cause significant denial-of-service conditions through crashes and instability in the rendering process.
This vulnerability aligns with Common Weakness Enumeration identifier CWE-416, which describes Use After Free errors where memory is accessed after it has been freed. In terms of offensive security frameworks, this exploit technique corresponds to ATT&CK tactic Tactic 07 for Defense Evasion and potentially Technique T1203 for Exploitation for Client Execution, as the goal is often to execute malicious payloads on the victim's machine through a trusted application like a web browser. Mitigation strategies primarily involve ensuring that all instances of Google Chrome are updated to version 154.0.8037.57 or later where these memory management issues have been rectified by developers who implemented stricter checks to prevent access to freed memory regions. Additionally, organizations should enforce strict policies regarding the opening of PDF files from untrusted sources and consider deploying browser isolation technologies to further reduce the attack surface associated with document rendering vulnerabilities.