DataBreaches.Net

Menu
  • About
  • Breach Notification Laws
  • Privacy Policy
  • Transparency Report
Menu

Investigation of 2024 Helsinki data breach – Report

Posted on June 17, 2025 by Dissent

There’s a follow-up to the Helsinki incident affecting hundreds of thousands of children and adults in 2024. The government has finished its investigation and published its findings and recommendations. From their press release:

The City of Helsinki’s Education Division (KASKO) was targeted by a serious data breach in spring 2024. As a consequence of the data breach, a large amount of data concerning learners and the City’s personnel ended up in the attacker’s hands. The documents on the hacked network drive additionally included data concerning other persons, companies and other partners who had had direct or indirect dealings with the City.”>The City of Helsinki’s Education Division (KASKO) was targeted by a serious data breach in spring 2024. As a consequence of the data breach, a large amount of data concerning learners and the City’s personnel ended up in the attacker’s hands. The documents on the hacked network drive additionally included data concerning other persons, companies and other partners who had had direct or indirect dealings with the City.

The attacker launched the data breach in mid-April 2024 and subsequently started mapping targets on the City’s intranet and expanding their access to different servers. At the end of April, the attacker copied a total of approx. two terabytes of data in four instalments from the network drive. Determining the exact number or contents of the files turned out to be impossible. The investigation concluded by estimating that the attacker gained access to approx. 750,000 documents, some of which contained sensitive personal data.”>The attacker launched the data breach in mid-April 2024 and subsequently started mapping targets on the City’s intranet and expanding their access to different servers. At the end of April, the attacker copied a total of approx. two terabytes of data in four instalments from the network drive. Determining the exact number or contents of the files turned out to be impossible. The investigation concluded by estimating that the attacker gained access to approx. 750,000 documents, some of which contained sensitive personal data.

The perpetrator managed to continue the attack for a long time as there were shortcomings in the organisation’s network monitoring, and the alerts received were not responded to in time. Once it had been confirmed that a data breach was underway, the City of Helsinki immediately launched management measures and repairs, which succeeded in stopping the attack.”>The perpetrator managed to continue the attack for a long time as there were shortcomings in the organisation’s network monitoring, and the alerts received were not responded to in time. Once it had been confirmed that a data breach was underway, the City of Helsinki immediately launched management measures and repairs, which succeeded in stopping the attack.

Two factors made copying a large volume of data possible: the information system was hacked through a VPN remote access server that was not maintained appropriately, and a large volume of data had accumulated on the network drive over several years. Shortcomings in maintenance resulted from personnel turnover and changes in the organisation, as a result of which the division of responsibilities remained ambiguous. Inadequate information management had led to the accumulation of data on the network drive, and compliance with instructions issued for network drive use was not supervised.”>Two factors made copying a large volume of data possible: the information system was hacked through a VPN remote access server that was not maintained appropriately, and a large volume of data had accumulated on the network drive over several years. Shortcomings in maintenance resulted from personnel turnover and changes in the organisation, as a result of which the division of responsibilities remained ambiguous. Inadequate information management had led to the accumulation of data on the network drive, and compliance with instructions issued for network drive use was not supervised.

While a number of acts and provisions apply to information management, awareness of them among practical actors is often low. The legislation and national guidelines are partly obscure and fragmented. The local government sector, in particular, is subject to obligations imposed by several different authorities, which makes them difficult to perceive as a whole.”>While a number of acts and provisions apply to information management, awareness of them among practical actors is often low. The legislation and national guidelines are partly obscure and fragmented. The local government sector, in particular, is subject to obligations imposed by several different authorities, which makes them difficult to perceive as a whole.

As a consequence of the data breach, a large number of documents containing personal data ended up in the attacker’s hands. The data can later be used for harmful purposes, including identity theft and fraud. No indications of such activity were detected during the investigation.”>As a consequence of the data breach, a large number of documents containing personal data ended up in the attacker’s hands. The data can later be used for harmful purposes, including identity theft and fraud. No indications of such activity were detected during the investigation.

The data breach had hundreds of thousands of victims. The investigation found that extensive identification of all victims was a challenge. While the City’s personnel could be reached easily, contacting previous employees and current and previous learners across the board was extremely challenging in practice, and no attempt at it was made.”>The data breach had hundreds of thousands of victims. The investigation found that extensive identification of all victims was a challenge. While the City’s personnel could be reached easily, contacting previous employees and current and previous learners across the board was extremely challenging in practice, and no attempt at it was made.

Four recommendations were issued as a result of the investigation. They are mainly addressed at the Ministry of Finance, which is responsible for implementing them together with the Ministry of Justice, Ministry of Transport and Communications, Finnish National Agency for Education and the Association of Finnish Local and Regional Authorities.”>Four recommendations were issued as a result of the investigation. They are mainly addressed at the Ministry of Finance, which is responsible for implementing them together with the Ministry of Justice, Ministry of Transport and Communications, Finnish National Agency for Education and the Association of Finnish Local and Regional Authorities.

  1. The Ministry of Finance in cooperation with the Ministry of Justice should ensure that the legislation on information management in public administration is coordinated and that the structures for monitoring and steering it are clarified.
  2. The Ministry of Finance in cooperation with the Ministry of Transport and Communications should investigate how the detection of information security deficiencies in public administration can be improved nationally and ensure that public actors have sufficient capabilities for detecting and addressing shortcomings in information security.
  3. The Ministry of Finance in cooperation with the Finnish National Agency for Education should ensure that municipalities and cities develop clear and accessible guidelines for communicating about data breaches, enabling victims to protect themselves from the consequences of data breaches and protect their personal data.
  4. The Ministry of Finance in cooperation with the Association of Finnish Local and Regional Authorities should support municipalities in identifying and addressing critical information security shortcomings and develop risk management relating to information management and information security.

P2024 Helsinki Investigation report [pdf, 6.7 MB]

h/t, Catalin Cimpanu


Related:

  • Qantas obtains injunction to prevent hacked data’s release
  • Ransomware attack disrupts Korea's largest guarantee insurer
  • Theft from Glasgow’s Queen Elizabeth University Hospital sparks probe
  • Global operation targets NoName057(16) pro-Russian cybercrime network in Operation Eastwood
  • More than 100 British government personnel exposed by Ministry of Defence data leak
  • New TeleMessage SGNL Flaw Is Actively Being Exploited by Attackers
Category: Breach Incidents

Post navigation

← Major trial underway for data leak that left 72,000 victims in France
Episource notifying 5.4 million patients of cyberattack in January →

Now more than ever

"Stand with Ukraine:" above raised hands. The illustration is in blue and yellow, the colors of Ukraine's flag.

Search

Browse by Categories

Recent Posts

  • UK sanctions Russian cyber spies accused of facilitating murders
  • Michigan ‘ATM jackpotting’: Florida men allegedly forced machines to dispense $107K
  • Premier Health Partners issues a press release about a breach two years ago. Why was this needed now?
  • Bitcoin holds steady as hackers drain over $40 million from CoinCDX, India’s top exchange
  • Government will ‘robustly defend’ compensation claims from Afghans put at risk by data breach
  • Authorities released free decryptor for Phobos and 8base ransomware
  • Singapore Facing ‘Serious’ Cyberattack by Espionage Group With Alleged China Ties
  • Missouri Adopts New Data Breach Notice Law
  • Qantas obtains injunction to prevent hacked data’s release
  • Ransomware attack disrupts Korea’s largest guarantee insurer

No, You Can’t Buy a Post or an Interview

This site does not accept sponsored posts or link-back arrangements. Inquiries about either are ignored.

And despite what some trolls may try to claim: DataBreaches has never accepted even one dime to interview or report on anyone. Nor will DataBreaches ever pay anyone for data or to interview them.

Want to Get Our RSS Feed?

Grab it here:

https://databreaches.net/feed/

RSS Recent Posts on PogoWasRight.org

  • Idaho agrees not to prosecute doctors for out-of-state abortion referrals
  • As companies race to add AI, terms of service changes are going to freak a lot of people out. Think twice before granting consent!
  • 𝐔𝐠𝐚𝐧𝐝𝐚 𝐨𝐫𝐝𝐞𝐫𝐬 𝐆𝐨𝐨𝐠𝐥𝐞 𝐭𝐨 𝐫𝐞𝐠𝐢𝐬𝐭𝐞𝐫 𝐚𝐬 𝐚 𝐝𝐚𝐭𝐚‑𝐜𝐨𝐧𝐭𝐫𝐨𝐥𝐥𝐞𝐫 𝐰𝐢𝐭𝐡𝐢𝐧 𝟑𝟎 𝐝𝐚𝐲𝐬 𝐚𝐟𝐭𝐞𝐫 𝐥𝐚𝐧𝐝𝐦𝐚𝐫𝐤 𝐩𝐫𝐢𝐯𝐚𝐜𝐲 𝐫𝐮𝐥𝐢𝐧𝐠.
  • Meta investors, Zuckerberg reach settlement to end $8 billion trial over Facebook privacy violations
  • ICE is gaining access to trove of Medicaid records, adding new peril for immigrants
  • Microsoft can’t protect French data from US government access
  • Texas Enacts Electronic Health Record Data Localization Law

Have a News Tip?

Email: Tips[at]DataBreaches.net

Signal: +1 516-776-7756

Contact Me

Email: info[at]databreaches.net

Mastodon: Infosec.Exchange/@PogoWasRight

Signal: +1 516-776-7756

DMCA Concern: dmca[at]databreaches.net
© 2009 – 2025 DataBreaches.net and DataBreaches LLC. All rights reserved.