CVE-2016-10187 in calibre
Summary
by MITRE
The E-book viewer in calibre before 2.75 allows remote attackers to read arbitrary files via a crafted epub file with JavaScript.
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Analysis
by VulDB Data Team • 10/24/2024
The vulnerability identified as CVE-2016-10187 resides within the e-book viewer component of calibre, a popular open-source e-book management and conversion tool. This issue affects versions prior to 2.75 and represents a critical security flaw that enables remote attackers to execute arbitrary file read operations through maliciously crafted epub files. The vulnerability specifically leverages JavaScript execution capabilities within the epub format to bypass normal file access controls and retrieve sensitive data from the underlying system.
This vulnerability stems from inadequate input validation and sanitization within the calibre e-book viewer's processing of epub files. When a user opens a specially crafted epub file containing malicious JavaScript code, the viewer fails to properly isolate the JavaScript execution environment from the host system's file system. The flaw allows the JavaScript to access file paths and read content from arbitrary locations on the device where calibre is installed, potentially exposing sensitive user data, system configuration files, or other confidential information stored on the local machine.
The operational impact of this vulnerability extends beyond simple information disclosure, as it represents a privilege escalation vector that can be exploited by remote attackers without requiring any local system access or user interaction beyond opening a malicious file. Attackers can craft epub files that contain JavaScript code designed to traverse the file system and read files that would normally be protected from unauthorized access. This capability creates significant risk for users who regularly download and open e-books from untrusted sources, as simply viewing a maliciously crafted epub file could result in data exfiltration.
The technical nature of this vulnerability aligns with CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal attacks. Additionally, this issue demonstrates characteristics of CWE-79, which addresses cross-site scripting vulnerabilities, as the JavaScript execution within the epub file enables arbitrary code execution in the context of the viewer application. From an attack framework perspective, this vulnerability would map to multiple ATT&CK techniques including T1059.007 for JavaScript execution and T1074 for data staging, as attackers could use this capability to gather information from compromised systems.
Mitigation strategies for CVE-2016-10187 primarily involve upgrading to calibre version 2.75 or later, which includes proper input validation and sandboxing measures for epub file processing. Users should also implement additional security measures such as avoiding opening e-books from untrusted sources, enabling strict content filtering in their e-book readers, and maintaining regular software updates to address similar vulnerabilities. Organizations should consider implementing network-based security controls to monitor for suspicious file transfers and ensure that users are running the latest versions of calibre to prevent exploitation of this and similar vulnerabilities in their environments.