CVE-2016-10403 in Chrome
Summary
by MITRE
Insufficient data validation on image data in PDFium in Google Chrome prior to 51.0.2704.63 allowed a remote attacker to perform an out of bounds memory read via a crafted PDF file.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 04/26/2020
The vulnerability identified as CVE-2016-10403 represents a critical security flaw within the PDFium library component of Google Chrome browsers. This issue stems from inadequate input validation mechanisms when processing image data within PDF documents, creating a pathway for remote attackers to exploit memory access violations. The vulnerability specifically affects Chrome versions prior to 51.0.2704.63, making it a significant concern for users operating outdated browser versions. The flaw manifests when the PDFium library fails to properly validate image data structures before attempting to read memory locations, potentially allowing attackers to access unauthorized memory regions.
The technical nature of this vulnerability aligns with CWE-125, which describes out-of-bounds read conditions where programs access memory locations beyond the intended buffer boundaries. When a malicious PDF file is processed by Chrome, the PDFium component attempts to parse image data without sufficient validation checks. This insufficient validation allows an attacker to craft specially formatted image data that triggers memory access violations, resulting in an out-of-bounds read operation. The attacker can potentially leverage this condition to read sensitive memory contents, which may include cryptographic keys, user credentials, or other confidential information depending on the memory layout at the time of access.
From an operational perspective, this vulnerability presents a severe risk to end users as it enables remote code execution through carefully crafted PDF documents. Attackers can exploit this flaw by delivering malicious PDF files through various attack vectors including email attachments, compromised websites, or malicious downloads. The remote exploitation capability means users do not need to perform any special actions beyond opening the malicious document, making it particularly dangerous in phishing campaigns and targeted attacks. The vulnerability operates at the memory management level, making it difficult to detect through traditional network-based security measures and requiring browser-level patches for remediation.
The attack surface for this vulnerability extends across all Chrome users who encounter malicious PDF files, with particular risk to organizations that receive PDF documents from external sources. Security professionals should consider this vulnerability in relation to ATT&CK technique T1204.002, which involves user execution of malicious files through social engineering tactics. The remediation strategy requires immediate browser updates to version 51.0.2704.63 or later, where Google implemented proper input validation mechanisms for image data processing. Organizations should also deploy network-based intrusion detection systems that can identify suspicious PDF file patterns and implement email filtering solutions to prevent delivery of potentially malicious documents. Additionally, user education regarding safe PDF handling practices and the importance of keeping software updated remains crucial in mitigating this class of vulnerability.