Stay secure with the latest email security updates, best practices, and threat alerts to protect your inbox and sensitive information.
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Background for this topic.
Email is a system for exchanging digital messages, typically using mail servers and clients over a network. In security, it includes both the messages and the accounts, servers, domains, and authentication mechanisms that handle them. Email commonly carries phishing links, malicious attachments, and fraudulent requests for payments or credentials; compromised accounts can also be used to impersonate trusted people and conduct further attacks.
Defenses include filtering and malware scanning, phishing-resistant multifactor authentication, careful handling of links and attachments, and monitoring for unusual login or sending activity. Domain controls such as SPF, DKIM, and DMARC help receiving systems detect messages that are forged or sent without authorization, while encryption protects message contents in transit or at rest when correctly implemented. Security teams should preserve relevant headers and mailbox activity so suspicious messages can be investigated, removed, and used to identify affected accounts and other recipients.
The move by the two giants means that DMARC, already in use by half of enterprises, will become table stakes for anyone using email for marketing, with all users set to benefit.
Defenders have been left scrambling after the way patches were released for six flaws in the open source mail server, which is the most popular mail transfer agent on the Internet.
Thousands of messages are being sent weekly in a campaign that uses links hosted on legitimate websites to evade natural language processing and URL-scanning email protections.