Clear, practical instructions for authenticating a sending domain with SPF, DKIM, and DMARC and why each matters for deliverability. SPF lists which sending IPs are allowed and is checked against the envelope sender (Return-Path), so forwarding often breaks SPF; DKIM adds a cryptographic signature whose public key lives in a DNS record under _domainkey and proves message integrity; DMARC ties SPF/DKIM results to the visible From address, requires alignment (relaxed or strict), and lets receivers apply a policy (none, quarantine, reject) and send reports. Misunderstanding which domain each check looks at is the common cause of failures: SPF/DKIM can pass for unrelated domains while DMARC fails.
Concrete setup advice and implementation caveats focus on using a dedicated sending subdomain (e.g., mail.example.com) and on correct DNS records. Publish DKIM selectors (Mailfully uses CNAMEs to host keys for rotation), set DKIM CNAMEs to DNS-only on Cloudflare, and verify with dig. Configure a custom MAIL FROM (send.mail.example.com) with MX and SPF TXT so SPF can align, remembering one SPF record per name and the 10-lookup limit. Watch DNS host forms to avoid appending the zone twice. Test both that records are published and that actual messages pass authentication.
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A federal judge in Oklahoma ruled that police using Flock's automated license plate reader system without a warrant violated the Fourth Amendment. The decision highlights concerns about the system's potential for indiscriminate mass surveillance, with over 100,000 warrantless searches conducted monthly. (404media.co)
ICE stored photos, license plates, and other data of protesters in a Palantir-built database called the Investigative Case Management system. Court filings reveal DHS agents used this database to track and intimidate observers during enforcement operations in Maine. (wired.com)
Apple will require explicit user actions for Mac apps to access full disk data, aiming to reduce security risks. This change comes as AI agents are deemed to substantially increase potential security vulnerabilities. (theverge.com)
Two vessels heading to the United States have been reportedly compromised by hackers. US officials are investigating the incidents involving these ships' cybersecurity breaches. (reuters.com)
A California tech executive has been arrested for allegedly smuggling $300 million worth of Nvidia chips to China. The case involves violations of export controls and sanctions related to the transfer of advanced semiconductor technology. (qz.com)
GrapheneOS fixed a major performance regression caused by Android 17 QPR1, which caused lag and freezes on Pixels. Google has been slow to release fixes for such issues, but GrapheneOS addressed it promptly and plans further improvements. (discuss.grapheneos.org)
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