CVE-2026-113026 in Chrome
Summary
by MITRE • 10/21/2026
Memory corruption in PDF in Google Chrome on on Android prior to 156.0.8078.47 allowed a remote attacker to potentially read memory inside the sandbox via a crafted HTML page. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 10/22/2026
The vulnerability described involves a critical memory corruption flaw within the PDF rendering engine of Google Chrome on Android, specifically affecting versions prior to 156.0.8078.47. This defect allows for arbitrary code execution or information disclosure under specific conditions, representing a significant security risk despite being classified with medium severity by Chromium teams. The core issue stems from improper handling of memory allocation and deallocation processes within the PDF parser component. When processing maliciously crafted HTML pages that embed PDF content, the browser fails to correctly manage buffer boundaries or validate input data structures before writing to them. This oversight leads to a heap-based buffer overflow or use-after-free condition, which corrupts adjacent memory regions in the process space.
From a technical perspective, this type of vulnerability is categorized under CWE-120 Buffer Copy without Checking Size of Input and CWE-416 Use After Free, depending on the exact mechanism exploited by attackers. The flaw resides deep within the rendering pipeline where PDF objects are parsed and rendered into visual elements for display. Attackers can craft an HTML page containing a specially constructed PDF file that triggers this memory corruption when loaded in Chrome's sandboxed renderer process. By carefully manipulating object sizes or pointers, an attacker can overwrite critical data structures such as function pointers or virtual table entries. This manipulation allows the attacker to redirect control flow to malicious shellcode injected into the heap, effectively bypassing standard security mitigations like ASLR and DEP that rely on memory layout integrity.
The operational impact of this vulnerability is substantial because it enables a remote attacker to potentially read sensitive information from inside the browser's sandboxed environment. While Chrome employs strict isolation between renderer processes and the main browser process, successful exploitation can lead to sandbox escape or direct data exfiltration if the corrupted memory contains pointers to higher-privilege contexts. An adversary could leverage this flaw to steal cookies, session tokens, saved passwords, or other confidential user data stored within the browser's local storage mechanisms. Furthermore, since the attack vector is a crafted HTML page, it can be delivered via phishing campaigns, malicious advertisements, or compromised websites without requiring any user interaction beyond visiting the URL, making it highly scalable and dangerous in real-world scenarios.
This vulnerability aligns with several tactics defined in the MITRE ATT&CK framework, particularly T1059 Command and Control Execution for running arbitrary code within the victim's environment and T1005 Data from Local System for exfiltrating information. The exploitation chain typically involves initial access through a malicious link, execution via the renderer process sandbox escape or direct memory read, and persistence if combined with other vulnerabilities to maintain foothold on the device. Given that Android devices are frequently targeted by mobile malware campaigns, this flaw provides a potent entry point for sophisticated threat actors aiming to compromise user privacy and security posture.
Mitigation strategies primarily focus on applying the latest software updates provided by Google. Users running Chrome versions prior to 156.0.8078.47 must update their browsers immediately to patch the underlying memory management issues in the PDF rendering engine. In addition to updating, organizations should enforce strict content security policies and utilize browser extensions that block potentially dangerous scripts or embedded objects from untrusted sources. Network-level defenses such as web application firewalls can also help filter out malicious payloads before they reach end-user devices. Security teams should monitor for indicators of compromise related to unusual memory usage patterns in Chrome processes, which may signal active exploitation attempts against this specific vulnerability class.