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.
A malicious third-party can give a crafted "ssh://..." URL to an unsuspecting victim, and an attempt to visit the URL can result in any program that exists on the victim's machine being executed. Such a URL could be placed in the .gitmodules file of a malicious project, and an unsuspecting victim could be tricked into running "git clone --recurse-submodules" to trigger the vulnerability.
Git before 2.10.5, 2.11.x before 2.11.4, 2.12.x before 2.12.5, 2.13.x before 2.13.6, and 2.14.x before 2.14.2 uses unsafe Perl scripts to support subcommands such as cvsserver, which allows attackers to execute arbitrary OS commands via shell metacharacters in a module name. The vulnerable code is reachable via git-shell even without CVS support.
Integer overflow in Git before 2.7.4 allows remote attackers to execute arbitrary code via a (1) long filename or (2) many nested trees, which triggers a heap-based buffer overflow.