Solved
- Debian websites use SSL certs verifiable by most existing OSes
- Some mirrors have https enabled and use SSL certs verifiable by most existing OSes
- Most suites have Valid-Until, preventing indefinite downgrade attacks
- SSL CA and DNSSEC/TLSA/DANE trust paths to Debian SSL certs
SSL connection to the Debian DNSSEC keys
Official mirror run by DSA on the Tor network (announcement, followup), unofficial ones run by Debian members too
- netboot.tar.gz are verifiable via the OpenPGP-signed Release files
win32-loader is verifiable via the OpenPGP-signed files called extrafiles
- deb.debian.org supports https
Issues
- No OpenPGP trust paths (ie Monkeysphere) to Debian or mirror SSL certs
- No OpenPGP trust paths to Debian DNSSEC keys
- Not available in browser certificate pinning (HPKP)
- Mirror updates are not authenticated in any way
- Most clients contacting mirrors reveal package names and version numbers
- Most mirrors probably have default apache2 logging (recording packages, versions, IPs etc)
- Mirrors list does not contain any info about https support
- Security update notices are via email
- No suggestions to or documentation about how to verify signatures
No downloads that use the subresource integrity for downloads standard.
- No magnet: links for bittorrent downloads on SSL
- No magnet: links for bittorrent downloads on OpenPGP-signed email
- No publishing of hashes of various things in Bitcoin/etc blockchains
- win32-loader is not Windows-code-signed
- win32-loader is not available in the Microsoft Windows Store
- no Debian installer is not available in the Apple Store or other popular stores
- ISO images server and mirrors have the same issues as repository mirrors
- Front page of Debian website links to an ISO image but no signature
- Verifying the ISO images is a convoluted process
- Torrent files for the ISO images are not able to be verified
BitErrant attacks on BitTorrent via SHA-1 collisions
- No ISO hashes available over HTTPS
- More prominent OpenPGP fingerprints for ISOs
- Preinstalled systems are not able to be verified
- Image downloader/writer programs that verify signatures and hashes
di-netboot-assistant does not verify things 775904
snapshot.debian.org validation requires turning off Valid-Until, using expired signatures and old keys, idea for a fix in 763419
SHA-1 is used in various places in Debian and by tools we use
Debian doesn't yet support binary transparency services (like Cothority
buildds do not verify source packages against developer keyrings