Hackers claim Rosstat leak shows up to 450,000 Russian war

Summary

Hacker groups Silent Crow and Cyber Partisans BY claim to have breached Rosstat, Russia's Federal State Statistics Service, stealing roughly 23 terabytes of data.
Analysis of the leaked death records points to Russian military deaths ranging from 393,881 to 450,100, well above a prior estimate of around 352,000.
Rosstat has confirmed a cyberattack occurred between October 29 and 31 but disputes the volume of data the hackers say they took.
The figures have not been independently verified, and Rosstat stopped publishing annual cause-of-death data in 2024.
The leak comes as the war approaches its fifth anniversary, with independent casualty estimates proving increasingly difficult to obtain.

Two hacker groups say they breached Russia's statistics agency and found death-registry data suggesting Russian military losses in Ukraine are far higher than previous estimates. Moscow confirms an attack took place but disputes the scale.

A pro-Ukrainian hacker collective and a Belarusian group say they have obtained internal Russian government data suggesting the true death toll among Russian soldiers in Ukraine is substantially higher than previously estimated, potentially approaching 450,000.

The groups, known as Silent Crow and Cyber Partisans BY, say they breached Rosstat, Russia’s Federal State Statistics Service, extracting around 23 terabytes of data that includes death-registry records from regional offices and a central data-processing centre, according to reporting by Mezha.net and Tom’s Hardware.

Competing figures, same source

The two groups have published separate analyses of the leaked records, arriving at different totals. Cyber Partisans BY counted 393,881 deaths it says can be explicitly tied to Russia’s military operation in Ukraine. Silent Crow’s broader analysis puts the figure at 450,100 deaths since February 2022, according to The New Voice of Ukraine and Euronews.

Both estimates are considerably higher than a widely cited prior figure of roughly 352,000, compiled by the independent outlets Meduza and Mediazona using Russian inheritance, or probate, records rather than government death data directly.

According to bne IntelliNews, the leaked data uses two cause-of-death codes consistent with war fatalities: one labelled Y36, for “operations of war,” and a broader code, Y89.1, covering around 38,229 recorded deaths. Reporters who reviewed the material say the war has become the fourth most common cause of death in Russia since 2022.

Rosstat confirms a breach, disputes the scale

Rosstat has acknowledged that its systems were hit by a coordinated cyberattack between October 29 and 31, but it disputes the hackers’ claim that tens of terabytes of data were taken. The agency has not addressed the specific casualty figures the hackers say they derived from its records.

“Access was gained to a large part of the IT infrastructure of the department, including the central office.” — Silent Crow, in a claimed statement reported by Mezha.net

Independent verification of the casualty figures remains impossible for now, as neutral third parties have not confirmed the data’s authenticity or completeness. The task has been complicated by Rosstat’s own decision, since 2024, to stop publishing its annual data on causes of death, a move that has made tracking Russian mortality trends harder for outside researchers.

The leak surfaced as the war in Ukraine approaches its fifth anniversary, a period in which independent casualty tracking has grown progressively more difficult. News outlets including The Moscow Times, Euronews and Stars and Stripes have reported on the claims, while cautioning that the underlying numbers remain unconfirmed by Moscow or independent observers.

This article was researched and drafted with AI assistance and reviewed by Lasse Pedersen before publication. How we use AI

This article is free to read. It always will be — no paywall, no account, no tracking.