It is unclear how successful these attempts have been, partly because Russian officials have never publicly acknowledged these intrusions. But a classified counterintelligence document from Russia’s domestic security agency, known as the F.S.B., makes clear that intelligence officials are concerned. The document, obtained by The New York Times, says that China is seeking Russian defense expertise and technology and is trying to learn from Russia’s military experience in Ukraine. The document refers to China as an “enemy.”, The hacking campaign shows that, despite this partnership and years of promises not to hack each other, China sees Russia as a vulnerable target. In 2023, one group, known as Sanyo, impersonated , The hacking campaign shows that, despite this partnership and years of promises not to hack each other, China sees Russia as a vulnerable target. In 2023, one group, known as Sanyo, impersonated the email addresses of a major Russian engineering firm in the hunt for information on nuclear submarines, according to TeamT5, a Taiwan-based .