NATO is investigating a new cyber attack claimed by the SiegedSec group

NATO is investigating claims that a group called SiegedSec has breached its systems and leaked a cache of unclassified documents online.

NATO announced it is investigating claims that a politically motivated threat actor called SiegedSec has breached its systems and leaked unclassified documents online.

“NATO cyber experts are actively addressing incidents affecting some unclassified NATO websites,” reads a statement issued by s NATO official to media outlets. “Additional cyber security measures have been put in place. There has been no impact on NATO missions, operations and military deployments.”

SiegedSec is a threat actor that last year carried out multiple attacks against U.S. organizations, especially U.S. municipalities.

On Saturday, September 30, 2023, the group announced on its Telegram channel the theft of approximately 3,000 North Atlantic Treaty Organization’ documents, more than 9 GB of data. The group published a series of screenshots showing access to hacked systems as proof of the hack.

SiegedSec Telegram channel

“The astonishing siegedsec hackers have struck NATO once more!!1!!! “we tend to have fun breaching intergovernmental alliances between large nations :p” the group wrote on Telegram. “We bring to you over 3 thousand files totaling to over 9GB of uncompressed Data!”

The official also confirmed that the Alliance has put in place additional cyber security measures, it also added that missions, operations and military deployments of the organization were not impacted.

The group claimed the hack of several portals run by NATO, including the Joint Advanced Distributed Learning, Lessons Learned Portal, Logistics Network Portal, Communities of of Interest Cooperation Portal, Investment Division Portal, and the Standardization Office.

In July, the SiegedSec group claimed the theft of another batch of documents from the organization’s Communities of Interest Cooperation Portal.

SiegedSec Telegram channel

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Pierluigi Paganini

(SecurityAffairs – North Atlantic Treaty Organization, SiegedSec)