CVE-2016-4271 in Flash Player
Summary
by MITRE
Adobe Flash Player before 18.0.0.375 and 19.x through 23.x before 23.0.0.162 on Windows and OS X and before 11.2.202.635 on Linux allows attackers to bypass intended access restrictions and obtain sensitive information via unspecified vectors, a different vulnerability than CVE-2016-4277 and CVE-2016-4278, aka a "local-with-filesystem Flash sandbox bypass" issue.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 09/16/2022
Adobe Flash Player contains a critical sandbox bypass vulnerability that affects multiple versions across different operating systems. This vulnerability specifically targets the local-with-filesystem sandbox protection mechanism that Flash Player employs to restrict file system access for local content. The flaw allows attackers to circumvent intended security boundaries and gain unauthorized access to sensitive information stored on the victim's local file system. The vulnerability operates through unspecified vectors that differ from related issues CVE-2016-4277 and CVE-2016-4278, making it a distinct threat vector within the broader Flash Player attack surface. This sandbox bypass represents a fundamental failure in Flash Player's security model, where local content that should be restricted from accessing the file system can potentially read arbitrary files and extract sensitive data.
The technical implementation of this vulnerability stems from insufficient validation of file system access permissions within Flash Player's runtime environment. When Flash Player processes local content, it typically enforces a strict sandbox policy that prevents local files from accessing the underlying file system without explicit user consent. However, this particular flaw allows malicious local content to bypass these restrictions through improper handling of file system operations. The vulnerability affects specific version ranges including Flash Player 18.0.0.375 and earlier, versions 19.x through 23.x before 23.0.0.162 on Windows and OS X, and versions before 11.2.202.635 on Linux. This widespread impact across multiple platforms and version ranges indicates a systemic issue within the Flash Player security architecture that required immediate attention.
The operational impact of this vulnerability is significant as it enables attackers to extract sensitive information from users' local systems. An attacker could potentially access personal documents, configuration files, cached data, and other locally stored information that should remain protected from unauthorized access. This type of information disclosure could lead to further exploitation opportunities, including credential theft, system reconnaissance, or data exfiltration. The vulnerability particularly affects users who visit malicious websites or open compromised local Flash content, as the attack can occur without requiring additional user interaction beyond normal browsing. From a threat actor perspective, this vulnerability represents a valuable tool for initial access and information gathering, as it allows for the extraction of locally stored sensitive data that could be used in subsequent attacks.
This vulnerability aligns with CWE-284, which describes improper access control mechanisms, and represents a classic sandbox escape scenario. The ATT&CK framework categorizes this as a privilege escalation technique where an attacker gains elevated access rights through bypassing security controls. Organizations should prioritize immediate patching of affected Flash Player versions to remediate this vulnerability. The recommended mitigation includes upgrading to patched versions of Flash Player, implementing network-based controls to block Flash content, and educating users about the risks associated with running outdated Flash Player components. Additionally, security monitoring should be enhanced to detect potential exploitation attempts through unusual file system access patterns or unexpected data transfers from compromised systems. Given the widespread use of Flash Player and the critical nature of the vulnerability, organizations should conduct thorough inventory assessments to identify all potentially affected systems and implement comprehensive remediation strategies across their environments.