Outlook.com hit by outages as hacktivists claim DDoS attacks

Outlook.com is suffering a series of outages today after being down multiple times yesterday, with hacktivists known as Anonymous Sudan claiming to perform DDoS attacks on the service.

This outage follows two major outages yesterday, creating widespread disruptions for global Outlook users, preventing users worldwide from reliably accessing or sending email and using the mobile Outlook app.

Outlook users have taken to Twitter to complain about the spotty email service, stating that it is affecting their productivity.

Microsoft says these outages are caused by a technical issue, posting to Twitter a series of updates switching between saying they mitigated the issues and saying that the problem is happening again. 

"We've identified that the impact has started again, and we're applying further mitigation," tweeted Microsoft.

"Telemetry indicates a reduction in impact relative to earlier iterations due to previously applied mitigations. Further details about the workstreams are in the admin center via MO572252."

Group claims to DDoS Microsoft Outlook

While Microsoft claims technical issues cause the outages, a group known as Anonymous Sudan is claiming to be behind them, warning that they are performing DDoS attacks on Microsoft to protest the US getting involved in Sudanese internal affairs.

"We can target any US company we want. Americans, do not blame us, blame your government for thinking about intervening in Sudanese internal affairs. We will continue to target large US companies, government and infrastructure," Anonymous Sudan posted to their Telegram channel yesterday.

"We hope you enjoyed it, Microsoft"

Since then, the group has been taunting Microsoft in statements about the repeated DDoS attacks on Microsoft Outlook and Microsoft 365 services.

"Microsoft, today we played football with your services. Let's play a fun game. The fate of your services, which is used by hundreds of millions of people everyday, is under our dominion and choice," Anonymous Sudan posted to their Telegram channel.

"You have failed to repel the attack which has continued for hours, so how about you pay us 1,000,000 USD and we teach your cyber-security experts how to repel the attack and we stop the attack from our end?"

From the check-host.net URLs shared by Anonymous Sudan, they say they are targeting "https://outlook.live.com/mail/0/," the main URL for the Outlook.com web service.

While these claims remain unverified, the service has been sluggish and plagued by a series of outages over the past 24 hours.

BleepingComputer contacted Microsoft about Anonymous Sudan's claims, but a response was not immediately available.