The vulnerability (CVE-2026-42284) exists in GitPython's _clone() method where multi_options are validated before being transformed by shlex.split. This allows an attacker to craft a string such as '--branch main --config core.hooksPath=/x' that passes the unsafe option check because the check uses startswith on the original list elements. After splitting, the '--config' option is passed to Git, which applies the configuration and executes attacker-controlled hooks during clone operations. This affects Repo.clone_from(), clone(), and Submodule.update() methods. The vulnerability is demonstrated by a proof-of-concept where a malicious hook is executed despite validation. The issue is similar in nature to CVE-2023-40267. The affected product is snowflake-cli using GitPython versions >=3.4.1 and <3.18.0.

Applications using snowflake-cli versions >=3.4.1 and <3.18.0 that pass user input to multi_options in GitPython clone operations are vulnerable. An attacker can embed unsafe Git options that bypass validation, leading to execution of arbitrary Git hooks. This can result in arbitrary code execution during repository cloning, compromising confidentiality, integrity, and availability of the affected system.

A patch is available for this vulnerability. Users should upgrade snowflake-cli to version 3.18.0 or later where this issue is fixed. Until then, avoid passing untrusted input to multi_options in GitPython clone operations. Follow the vendor advisory for official remediation guidance.