Finland's Transport and Communications Agency has issued a serious warning about Microsoft 365 account breaches. The agency reports a sharp increase in attacks targeting organizational accounts.
Traficom's Cybersecurity Center first warned about these breaches in September. The warning applies to all Finnish companies and organizations using M365 environments, plus their employees and users.
The center received 120 reports about M365 account breaches in October. That follows 117 reports received in September.
Cybersecurity expert Samuli Könönen said email account takeovers are accelerating. He called the trend deeply concerning.
Mass exploitation of compromised accounts poses particular risks, Könönen explained. Attackers use hijacked accounts to send new phishing messages to contacts.
Traficom urges organizations to activate M365 security features immediately. Recommended measures include conditional access controls and passwordless authentication methods.
Identifying phishing messages from familiar accounts requires extra vigilance, Könönen noted. Organizations must protect employees by implementing available security tools.
The consecutive monthly increases suggest attackers are refining their techniques against Finnish targets. Basic security measures no longer provide sufficient protection against these coordinated campaigns.