Git before 1.8.5.6, 1.9.x before 1.9.5, 2.0.x before 2.0.5, 2.1.x before 2.1.4, and 2.2.x before 2.2.1 on Windows and OS X; Mercurial before 3.2.3 on Windows and OS X; Apple Xcode before 6.2 beta 3; mine all versions before 08-12-2014; libgit2 all versions up to 0.21.2; Egit all versions before 08-12-2014; and JGit all versions before 08-12-2014 allow remote Git servers to execute arbitrary commands via a tree containing a crafted .git/config file with (1) an ignorable Unicode codepoint, (2) a git~1/config representation, or (3) mixed case that is improperly handled on a case-insensitive filesystem.

Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.

A flaw was found in Mercurial before 4.9. It was possible to use symlinks and subrepositories to defeat Mercurial's path-checking logic and write files outside a repository.

cext/manifest.c in Mercurial before 4.7.2 has an out-of-bounds read during parsing of a malformed manifest entry.

mpatch.c in Mercurial before 4.6.1 mishandles integer addition and subtraction, aka OVE-20180430-0002.

The mpatch_apply function in mpatch.c in Mercurial before 4.6.1 incorrectly proceeds in cases where the fragment start is past the end of the original data, aka OVE-20180430-0004.

The mpatch_decode function in mpatch.c in Mercurial before 4.6.1 mishandles certain situations where there should be at least 12 bytes remaining after the current position in the patch data, but actually are not, aka OVE-20180430-0001.

Mercurial version 4.5 and earlier contains a Incorrect Access Control (CWE-285) vulnerability in Protocol server that can result in Unauthorized data access. This attack appear to be exploitable via network connectivity. This vulnerability appears to have been fixed in 4.5.1.

In Mercurial before 4.4.1, it is possible that a specially malformed repository can cause Git subrepositories to run arbitrary code in the form of a .git/hooks/post-update script checked into the repository. Typical use of Mercurial prevents construction of such repositories, but they can be created programmatically.

Mercurial prior to version 4.3 is vulnerable to a missing symlink check that can malicious repositories to modify files outside the repository