Superior Tribunal de Justiça

Summary

The Brazilian Superior Court of Justice experienced acyber attack that caused its portal to become unstable, prompting the implementation of a pre‑access validation page to mitigate a possible denial of service attempt. The institution reported that its security tools identified and blocked the intrusion attempts, preventing any disruption to its systems or services. Officials noted that similar incidents have occurred before, though the latest event was contained without affecting judicial operations.

Motives

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TTPs

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Description

On March4, 2025, the Superior Tribunal de Justiça (STJ) reported being targeted by a cyberattack that began within the previous 48 hours. The attack caused the institution’s portal to become unstable and difficult for users to access. Starting on the morning of Tuesday, March 4, anyone attempting to reach the STJ portal was first directed to a pre‑validation page before being allowed to proceed to the site. The tribunal’s technology sector explained that this validation step was activated to thwart a potential denial‑of‑service (DoS) attack. A DoS attack attempts to overwhelm servers with an excessive number of access requests, which can force a website offline. The STJ stated that the human‑user validation mechanism may cause slower response times but does not compromise the portal’s functionality or services. The tribunal’s cybersecurity tools detected the intrusion attempts and blocked them before any damage could occur. Officials confirmed that the STJ’s systems were not taken down as a result of the attack.

This incident is not the first time the STJ has faced cyber threats; a similar episode in September 2024 temporarily paralyzed the tribunal’s systems for several minutes. Earlier, in 2020, a cyber offensive disrupted judicial proceedings and impaired the operation of the judicial systems for approximately five days. In both prior cases, the attacks affected access to case information and delayed judicial activities. The STJ emphasized that, unlike the 2020 event, the March 2025 attack was contained without causing lasting disruption to its services. The tribunal credited its preventive security tools and the pre‑validation measure for successfully neutralizing the threat. No further details about the attackers or their motives were disclosed in the available source.

Sources

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