Git Security Vulnerability Remediation

This thread tracks the evolution of Git security vulnerability remediation. Initially, it focused on a critical Git security vulnerability (CVE 2018-11235) that could lead to arbitrary code execution. The fix involved updating Git clients to version 2.17.1 and implementing server-side checks in Visual Studio Team Services (VSTS) to block malicious repositories. The vulnerability arose from how Git handles submodules, allowing specially crafted repositories to execute post-checkout hooks. The solution restricts submodule folder names to prevent malicious paths. This post details a new vulnerability (CVE 2017-1000117) related to Git URL parsing and embedded command-line options, particularly affecting submodules. It outlines the problem where malicious URLs can execute arbitrary code via SSH's ProxyCommand functionality, and the solution which involves examining submodule URLs more closely to block those that begin with a hyphen ('-') and resemble command-line options.