Security and accounts
idmsa.apple.com
idmsa.apple.com and gsa.apple.com authenticate your Apple Account. Apple says that this is required for every service that uses an Apple Account, such as iCloud, app installs and Xcode.
Short answer
Apple's Apple Account authentication hosts. Signing in to iCloud, the App Store and Xcode needs them.
Don’t block
Don't block them. Signing in to your Apple Account fails, and with it iCloud, the App Store and Xcode sign-in.
- Matches
idmsa.apple.comgsa.apple.com
A name with *. covers every name under it: *.push.apple.com matches 1-courier.push.apple.com.
What it serves
Apple's enterprise host list names both in its Apple Account section, for “Apple Account authentication”, on port 443, with proxy support.
Apple says that devices must reach the Apple Account hosts to authenticate an Apple Account.
On a Mac, Apple Account sign-in goes through AuthKit, whose daemon is akd. Apple doesn't document which process contacts which host.
Processes that use it
What breaks if you block it
Don’t block
Don't block them. Signing in to your Apple Account fails, and with it iCloud, the App Store and Xcode sign-in.
What breaks if you block it
- Signing in to iCloud, the App Store, Xcode and other Apple services fails.
- Two-factor checks and password confirmations may fail.
With Kilobat Pro and the network filter, you can block a host for every app or for one app: in Connections, select a connection and choose Block. Apple’s own services are never blocked by Kilobat’s Protection lists.
Apple’s rules for its hosts
Apple’s list, Use Apple products on enterprise networks, says that devices open these connections, not Apple’s servers. Apple services fail any connection that uses HTTPS interception, so a proxy that inspects TLS should leave Apple’s hosts alone.
If a firewall allows hosts by name, allowing *.apple.com covers most Apple services, Apple says. A firewall that works only with addresses can allow 17.0.0.0/8 for IPv4, and 2403:300::/32, 2620:149::/32 and 2a01:b740::/32 for IPv6.
To see which app on your Mac opened a connection to this host, use Kilobat’s Connections tab, or the agent network log for AI agents.
Sources
- Apple Support: Use Apple products on enterprise networks
- Apple Platform Security: Apple Account security
Checked on 1 November 2026.