Hackers copied 26,000 internal documents from city of Vienna
Vienna's city government said hackers copied about 26,000 internal documents, including data on roughly 6,000 people, in a cyberattack detected in early September.
The city of Vienna was the victim of a cyberattack in which unknown hackers gained access to its IT systems and copied about 26,000 internal documents, Vienna's chief information officer Klemens Himpele told the Austrian press agency APA. Data belonging to around 6,000 people was among the material copied, though there is no indication so far that it has been published.
Austria's Computer Emergency Response Team first alerted city hall to the breach on 9 September, Der Standard reported. Access to a vulnerability in the city's system had reportedly been offered for sale on an online forum beforehand; the flaw was later identified and closed with help from Austria's domestic security and intelligence directorate, DSN.
An analysis found that the attacker or attackers had gained access to an internal documentation platform that held training material and project documentation, according to both outlets. A specialised scanning tool is suspected to have found the vulnerability to carry out what is known as a data breach; a phishing attack has currently been ruled out. Himpele said no one gained control of the city's systems or user accounts at any point, and there was no direct access to the city's wider IT network.
In total, 26,000 documents amounting to nine gigabytes were copied, containing data on about 2,000 municipal employees, roughly 2,900 residents and more than 800 contractors, Der Standard and Kurier reported. In most cases only names or email addresses were exposed, though in some cases more sensitive data, such as sick-leave records or IBAN numbers, may also have been duplicated.
The city said the stolen information had not, to its current knowledge, been published, and that it had not been extorted for money. The breach was reported to Austria's data protection authority, and affected individuals are being notified. "We can only apologise," Himpele said.
Harald Zierfuß, a city councillor for the Vienna People's Party, said an attack of this scale had to be taken very seriously and called for full transparency on how the security gap arose and whether it could have been detected or prevented earlier.
The breach came weeks after a separate hack of data held by the city of Berlin, which included Berlin fire brigade hazard-protection data, payroll lists, account information and staff disciplinary records; the hackers demanded €2 million from Berlin, which was not paid, and parts of the data later appeared on the dark web, Kurier reported.
What we know
- Hackers copied about 26,000 internal documents, totalling nine gigabytes, from the city of Vienna's IT systems, city CIO Klemens Himpele said.
- Data belonging to around 6,000 people, mostly names and email addresses, was among the material copied; some sick-leave records and IBAN numbers may also have been duplicated.
- The breach was first flagged by Austria's Computer Emergency Response Team on 9 September; the vulnerability has since been closed.
- The city said there is no indication the stolen data has been published and that it was not extorted for money.
- A similar hack hit the city of Berlin weeks earlier; Berlin did not pay a €2 million ransom demand and some of its data later appeared on the dark web.
Not yet confirmed
- Who was behind the attack has not been established.
Why it matters for Europe
The breach exposed personal data on roughly 6,000 people connected to Vienna's city administration, from staff to residents and contractors, even though officials say attackers never gained control of the city's core IT systems. It follows a similar attack on Berlin's city government weeks earlier, in which stolen data appeared on the dark web after a ransom went unpaid, illustrating the same kind of vulnerability now facing more than one major European city administration.
Sources
Reported by 2 reports from 2 independent outlets in 1 countries.
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Questions and answers
- What happened in the Vienna cyberattack?
- Hackers gained access to an internal documentation platform and copied about 26,000 documents, including data on roughly 6,000 people, city CIO Klemens Himpele said.
- Was any of the stolen data published?
- The city said there is no indication so far that the data has been published, and that it was not extorted for a ransom.
- How does this compare to the Berlin hack?
- Berlin's city government was hacked weeks earlier; it did not pay a €2 million ransom demand, and part of the stolen data later appeared on the dark web.
This article was written with AI assistance from 2 verified reports and checked under the ECTV editorial policy. Spotted an error? Request a correction.