Insufficiently-secured technologies deployed in critical space infrastructures represent a major attack surface whose exploitation will likely trigger a sequence of catastrophic incidents. Compounded by the race for commercialization of outer space and the lack of an oversight agency responsible for securing space assets, threats stemming from cyberspace have the potential to translate into attacks, conflicts, or even warfare conducted in outer space. This paper aims at examining the ensuing significant legal ramifications of such incidents involving State and non-State actors under international law. To that end, it employs a concrete cyberattack scenario where a commercial satellite with thrusters is captured by cyber means and weaponized into something that can disrupt ongoing military operations and destruct other space assets. It then delves deep into the legal characterization of the cyberattack in question as well as its attribution to a State and/or non-State actor under the law on State responsibility with respect of ‘attribution’.