Advisories for Cargo/Gix-Transport package

gix-transport does not check the username part of a URL for text that the external ssh program would interpret as an option. A specially crafted clone URL can smuggle options to SSH. The possibilities are syntactically limited, but if a malicious clone URL is used by an application whose current working directory contains a malicious file, arbitrary code execution occurs.

The gix-transport crate prior to the patched version 0.36.1 would allow attackers to use malicious ssh clone URLs to pass arbitrary arguments to the ssh program, leading to arbitrary code execution. PoC: gix clone 'ssh://-oProxyCommand=open$IFS-aCalculator/foo' This will launch a calculator on OSX. See https://secure.phabricator.com/T12961 for more details on similar vulnerabilities in git. Thanks for vin01 for disclosing this issue.