Git before 2.14.5, 2.15.x before 2.15.3, 2.16.x before 2.16.5, 2.17.x before 2.17.2, 2.18.x before 2.18.1, and 2.19.x before 2.19.1 allows remote code execution during processing of a recursive "git clone" of a superproject if a .gitmodules file has a URL field beginning with a '-' character.
In Git before 2.13.7, 2.14.x before 2.14.4, 2.15.x before 2.15.2, 2.16.x before 2.16.4, and 2.17.x before 2.17.1, code to sanity-check pathnames on NTFS can result in reading out-of-bounds memory.
In Git before 2.13.7, 2.14.x before 2.14.4, 2.15.x before 2.15.2, 2.16.x before 2.16.4, and 2.17.x before 2.17.1, remote code execution can occur. With a crafted .gitmodules file, a malicious project can execute an arbitrary script on a machine that runs "git clone --recurse-submodules" because submodule "names" are obtained from this file, and then appended to $GIT_DIR/modules, leading to directory traversal with "../" in a name. Finally, post-checkout hooks from a submodule are executed, bypassing the intended design in which hooks are not obtained from a remote server.
GIT version 2.15.1 and earlier contains a Input Validation Error vulnerability in Client that can result in problems including messing up terminal configuration to RCE. This attack appear to be exploitable via The user must interact with a malicious git server, (or have their traffic modified in a MITM attack).
Git through 2.14.2 mishandles layers of tree objects, which allows remote attackers to cause a denial of service (memory consumption) via a crafted repository, aka a Git bomb. This can also have an impact of disk consumption; however, an affected process typically would not survive its attempt to build the data structure in memory before writing to disk.