Mercurial vulnerabilities

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

In Mercurial before version 4.1.3, the command 'hg serve --stdio' allows remote authenticated users to launch the Python debugger, consequently executing arbitrary code by using --debugger as a repository name.

The binary delta decoder in Mercurial before version 3.7.3 allows remote attackers to execute arbitrary code via (1) clone, (2) push, or (3) pull commands, related to (a) a list sizing rounding error and (b) short records.

Mercurial before 3.7.3 allows remote attackers to execute arbitrary code via a crafted name when converting a Git repository.

Mercurial before 3.7.3 allows remote attackers to execute arbitrary code via a crafted git ext:: URL when cloning a subrepository.

The _validaterepo function in sshpeer in Mercurial before version 3.2.4 allows remote attackers to execute arbitrary commands via a crafted repository name in a clone command.

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

Mercurial prior to 4.3 did not adequately sanitize hostnames passed to ssh, leading to possible shell-injection attacks.