Ukrainian hacking group Ukrainian Militant said in a Sept. 17 Telegram post that it had obtained a large cache of technical documents on Russian naval projects. The materials it published include documents from 2024 to 2026 on navigation systems for Russia’s Project 636.3 Varshavyanka-class attack submarines, Project 955M Borei-A ballistic missile submarines, and Project 22350 frigates.
The operation was dubbed “Poseidon.” The hackers said they obtained scientific, technical, design, testing, and operational documentation from Russian companies developing systems for the navy. They said the cache includes documents marked “secret” and “top secret.” The full scale and contents of the documents could not be independently verified.
Screenshots published by Ukrainian Militant show documents from the Rubin Central Design Bureau for Marine Engineering, among others. One example from 2024 concerns development work on the Andoga-M2 navigation system with “advanced positional correction capabilities” for Project 636.3 submarines. Another, dated 2025, concerns development of a modified navigation system for Project 955M nuclear-powered submarines.
Another published document, dated March 2026, concerns the results of interagency testing of the Simfoniya-PM navigation system. Among other things, it says the stability of navigation data generated by the onboard inertial navigation system after maneuvers needs to be improved, as does the system’s interaction with other onboard equipment.
The published materials also include a test program for the Chardash-22350 automated navigation and gyro-stabilization system for a Project 22350 frigate, as well as documentation for the KAMA integrated marine navigation and stabilization system.
Despite the terminology, these are not simply shipboard “navigation devices.” A submarine that is underwater cannot rely on GPS, meaning it has to calculate its position independently and periodically correct its coordinates by other means. Some of the published documents concern newer methods of correcting navigation data.
Ukrainian Militant said the full cache is far broader than the excerpts released publicly and that the larger trove includes technical specifications and requirements, operating manuals, structural and functional diagrams, algorithms, accuracy and reliability parameters, test programs and results, and acceptance documents.
According to the group, the obtained documents cover not only navigation but also sonar, digital hydrography, marine robotics, and autonomous navigation for underwater vehicles. The systems mentioned include Simfoniya, Chardash, KAMA-NS-VK, Sprut-N1, Priliv, and 14Ts217, among others.
The hackers also said the documentation as a whole makes it possible to trace the work of Russian specialists across 70 projects involving ships, vessels, and submarines under construction or modernization. Organizations whose materials were said to be included in the cache include the Rubin Central Design Bureau for Marine Engineering, the Malachite Marine Engineering Bureau, the Elektropribor Central Research Institute, the Okeanpribor concern, Elara, the Vega concern, and the State Research Navigation and Hydrographic Institute.
