MEO announces 'mass attack' after outages in Portugal: Says no access to customer data

After many users reported problems with internet and telecommunications services in Portugal on Monday evening, MEO announced that its infrastructure was the target of a "massive attack". The company reported that the attack caused congestion and decreased service quality in its international network, but did not access customer data.

On the evening of September 14, in addition to MEO, Vodafone, NOS and Digi users received many reports of problems with the internet and other services.

However, there is no confirmed information that the attack announced by MEO is also the cause of the problems reported by other operators. Therefore, there is not enough data at this stage to attribute all outages across the country to a single cyber attack.

MEO: Our international network was targeted

According to the statement made by MEO to Lusa, the company encountered a large-scale attack on its international network, which caused “congestionamento e degradação”, that is, congestion and performance degradation.

The operator reported that mitigation and recovery measures were put in place and services were stabilized following the incident.

The company did not disclose details about the technical type of the attack, its source or the identity of the attackers.

Therefore, it is not possible at this stage to ascertain the nature of the incident beyond MEO's public statement.

Has customer data been compromised?

MEO's statement According to no.

The company states that as a result of the incident, there was no unauthorized entry into its systems and no data belonging to MEO or its customers was accessed.

This distinction is important. Just because a telecommunications service slows down or becomes inaccessible as a result of an attack does not necessarily mean that attackers have penetrated the company's internal systems or captured customer data.

The information made public so far does not indicate a data breach.

Problems reported on other operators as well

Downdetector data showed an increase in user notifications for other operators, including Vodafone, NOS and Digi, at the same time.

However, these reports are based on user reports and do not alone prove that all operators are affected by the same technical incident.

Therefore, additional technical information is required to establish a direct connection between the attack confirmed by MEO and the outages in other operators.

Resources

MEO statement / Lusa, transferred by RTP — 14 September 2026

https://www.rtp.pt/noticias/cultura/meo-alvo-de-ataque-em-massa-garante-que-nao-houve-acesso-a-dados-de-clientes_n1765431

Diário de Notícias / Lusa — 14 September 2026

https://www.dn.pt/sociedade/meo-foi-alvo-de-ataque-em-massa-mas-garante-que-no-houve-acesso-a-dados-de-clientes

ECO — September 14, 2026

https://eco.sapo.pt/2026/09/14/operadoras-de-telecomunicacoes-registam-falhas-no-acesso-a-internet-em-todo-o-pais/