go-git clients vulnerable to DoS via maliciously crafted Git server replies

Impact

A denial of service (DoS) vulnerability was discovered in go-git versions prior to v5.13. This vulnerability allows an attacker to perform denial of service attacks by providing specially crafted responses from a Git server which triggers resource exhaustion in go-git clients.

This is a go-git implementation issue and does not affect the upstream git cli.

Patches

Users running versions of go-git from v4 and above are recommended to upgrade to v5.13 in order to mitigate this vulnerability.

Workarounds

In cases where a bump to the latest version of go-git is not possible, we recommend limiting its use to only trust-worthy Git servers.

Credit

Thanks to Ionut Lalu for responsibly disclosing this vulnerability to us.