CVE-2017-8314 in Kodi
Summary
by MITRE
Directory Traversal in Zip Extraction built-in function in Kodi 17.1 and earlier allows arbitrary file write on disk via a Zip file as subtitles.
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Analysis
by VulDB Data Team • 12/07/2022
The vulnerability identified as CVE-2017-8314 represents a critical directory traversal flaw within the Kodi media center software version 17.1 and earlier. This security weakness resides in the built-in zip extraction functionality that Kodi employs for processing subtitle files. The vulnerability stems from insufficient input validation and sanitization when handling compressed archive files, particularly those containing subtitle content. Attackers can exploit this flaw by crafting malicious zip files that contain specially formatted path references designed to traverse directories and write files to arbitrary locations on the target system.
The technical implementation of this vulnerability involves the improper handling of path traversal sequences within zip file entries. When Kodi processes a zip file containing subtitles, it fails to adequately sanitize the file paths extracted from the archive. This allows attackers to include entries with paths such as ../../etc/passwd or similar constructs that would normally be prevented by proper path validation mechanisms. The flaw specifically affects the subtitle extraction process where Kodi automatically extracts and installs subtitle files from zip archives without sufficient security checks. This behavior creates a scenario where malicious actors can manipulate the extraction process to write files outside of the intended directory structure, potentially overwriting critical system files or installing malware.
The operational impact of this vulnerability is significant as it provides attackers with arbitrary file write capabilities on systems running vulnerable versions of Kodi. An attacker who can convince a user to download and install a malicious subtitle zip file could potentially overwrite system binaries, install backdoors, or modify configuration files to maintain persistent access. The vulnerability is particularly dangerous because subtitle files are commonly downloaded from third-party sources and automatically processed by Kodi without user intervention. This makes it possible for attackers to silently compromise systems simply by distributing malicious zip files through legitimate subtitle distribution channels.
This vulnerability aligns with CWE-22 Directory Traversal and maps to several ATT&CK techniques including T1059 Command and Scripting Interpreter and T1078 Valid Accounts. The attack vector leverages the trust users place in subtitle files and the automatic processing capabilities of media center applications. Organizations and individuals running vulnerable versions of Kodi are at risk of privilege escalation and persistent malware installation. The vulnerability demonstrates how seemingly benign file processing functions can become attack vectors when proper input validation is absent. Security practitioners should note that this flaw represents a classic example of insufficient path validation in archive processing functions, which is a common pattern in many software applications. The remediation approach requires immediate patching of Kodi to version 17.2 or later, where the zip extraction logic has been properly hardened against directory traversal attacks.