CVE-2017-5397

CVE-2017-5397 describes a critical vulnerability in Mozilla Firefox versions prior to 51.0.3, where the browser's local file system cache directory is world-writable. This misconfiguration allows a malicious application or attacker with file system write access to replace legitimate Firefox libraries with their own, leading to arbitrary code execution. With a CVSS score of 9.8 (Critical), this vulnerability presents a significant risk due to its network-exploitable nature, low attack complexity, and high impact on confidentiality, integrity, and availability. While there is no evidence of active exploitation or publicly available exploit code in Metasploit, Nuclei, or ExploitDB, the vulnerability has garnered some community discussion, indicating awareness within the cybersecurity community.