Cursor Vulnerability (CVE-2025-59944): How a Case-Sensitivity Bug Exposed the Risks of Agentic Developer Tools

A vulnerability identified as CVE-2025-59944 was discovered by Lakera researcher Brett Gustafson in Cursor, an AI-driven IDE that allows developers to write code using natural language, highlighting the potential risks associated with agentic developer tools. The flaw involved a case-sensitivity bug that enabled attackers to bypass file protections, potentially allowing unauthorized modifications to configuration files and leading to remote code execution. Cursor's protection logic, which matched filenames case-sensitively, failed on case-insensitive filesystems like those on Windows and macOS, allowing crafted inputs to exploit this loophole. Although the issue was swiftly addressed in Cursor 1.7 by normalizing file paths and comparing them without case sensitivity, the incident underscores the evolving challenges in software security as AI tools gain more autonomy. This case illustrates the necessity for security measures to focus on understanding intent rather than just syntax, as automation expands the attack surface of development environments, necessitating a shift from static validation to behavioral and contextual defense.