CVE-2016-5206 in Chrome
Summary
by MITRE
The PDF plugin in Google Chrome prior to 55.0.2883.75 for Mac, Windows and Linux, and 55.0.2883.84 for Android incorrectly followed redirects, which allowed a remote attacker to bypass the Same Origin Policy via a crafted HTML page.
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Analysis
by VulDB Data Team • 05/14/2026
The vulnerability identified as CVE-2016-5206 represents a critical security flaw in Google Chrome's PDF plugin implementation across multiple platforms including Mac, Windows, Linux, and Android. This issue stems from the improper handling of HTTP redirects within the browser's PDF rendering component, creating a significant bypass opportunity for malicious actors. The flaw specifically affects Chrome versions prior to 55.0.2883.75 for desktop platforms and 55.0.2883.84 for Android, making it a widespread concern for users of these browser versions.
The technical root cause of this vulnerability lies in the PDF plugin's failure to properly validate redirect chains when processing maliciously crafted HTML pages. When a user visits a specially constructed webpage containing embedded PDF content with redirect directives, the plugin follows these redirects without adequate security checks. This behavior violates fundamental web security principles by allowing content from different origins to be loaded and executed within the same security context where it should be restricted. The Same Origin Policy, which serves as a cornerstone of web security by preventing unauthorized access to resources across different origins, becomes effectively circumvented through this flaw.
The operational impact of CVE-2016-5206 extends beyond simple privilege escalation, creating opportunities for sophisticated attacks that could compromise user data and system integrity. Attackers can craft HTML pages that appear legitimate while secretly loading malicious PDF content from different origins, potentially enabling cross-site scripting attacks, data exfiltration, or the execution of arbitrary code. This vulnerability particularly affects users who frequently access untrusted websites or receive suspicious email attachments containing PDF documents, as the attack can occur silently in the background without user awareness.
Security researchers have classified this vulnerability under CWE-200, which addresses "Information Exposure," and it aligns with ATT&CK techniques related to privilege escalation and initial access through web-based attacks. The flaw demonstrates how seemingly minor implementation details in browser components can create significant security holes that undermine the entire security model of modern web browsers. Organizations and individuals should prioritize updating to patched versions of Chrome immediately, as the vulnerability provides attackers with a straightforward method to bypass core web security protections. The incident highlights the importance of rigorous security testing for browser plugins and components that handle external content, particularly those that interact with network protocols and redirect mechanisms.