4 ms·

This is why I've blocked all HTTP traffic outgoing from my machines. A lot of people have brought this up over the years: https://www.reddit.com/r/AMDHelp/com

• bflesch 8mo ago
  AFAIK a lot of linux packet repositories are http-only as well. Convenient for tracking what package versions have been installed on a certain system.
  • arghwhat 8mo ago
    They usually support both, but important to note that HTTPS is only used for privacy. Package managers generally enforce authenticity through signed indexes and (directly or indirectly) signed packages, although be skeptical when dealing with new/minor package managers as they could have gotten this wrong.
    • Avamander 8mo ago
      Reducing the benefit of HTTPS to only privacy is dishonest. The difference in attack surface exposed to a MITM is drastic, TLS leaves so little available for any attacker to play with.
      • mldbk 8mo ago
        MITM usually will not work in case of pkg managers, since packages are signed. But still, attacker can learn what kind of software is installed on target. So I believe that HTTPS for privacy in case of linux package managers are fair enough.
        • Avamander 8mo ago
          The attacker can meddle with every step taken before the signature verification. The way you handle the HTTP responses, the way you handle the signature format, all that. Captive portals have already caused corruption issues for Apt, signed packages be damned. Saying it's "fair" is like saying engine maintenance does not matter because the tires are inflated. There are more components to it. Ensuring the correctness of your entire stack against an active MITM is significantly more difficult than ensuring the correctness of just a TLS stack against an active MITM.
• arghwhat 8mo ago
  > Potentially it's even a way for a MITM to exploit the HTTP stack, some content parser or the application's own handling. TLS stacks are a significantly harder target in comparison. For signed payloads there is no difference, you're trusting <client>'s authentication code to read a blob, a signature and validate it according to a public key. For package managers that usually only mean trusting gpg - at the very least no less trustworthy than the many TLS and HTTP libraries out there.
  • inetknght 8mo ago
    > For signed payloads there is no difference, you're trusting <client>'s authentication code to read a blob, a signature and validate it according to a public key. Assuming this all came through unencrypted HTTP: - you're also trusting that the client's HTTP stack is parsing HTTP content correctly - for that matter, you're also trusting that the server (and any man-in-the-middle) is generating valid HTTP responses - you're also trusting that the client's response parser doesn't have a vulnerability (and not, say, ignoring some "missing closing bracket" or something) - you're also trusting that the client is parsing the correct signature (and not, say, some other signature that was tacked-on later) It's trivially easy to disassemble software to find vulnerabilities like those, though. So it's a lot of trust given for an untrusted software stack.
    • arghwhat 8mo ago
      > you're also trusting that the client's HTTP stack is parsing HTTP content correctly This is an improvement: HTTP/1.1 alone is a trivial protocol, whereas the alternative is trusting the client's much more complicated TLS stack and its HTTP stack. For technical reasons, unencrypted HTTP is also always the simpler (and for bulk transfers more performant) HTTP/1.1 in practice as standard HTTP/2 dictates TLS with the special non-TLS variant ("h2c") not being as commonly supported. > for that matter, you're also trusting that the server (and any man-in-the-middle) is generating valid HTTP responses You don't, just like you don't trust a TLS server to generate valid TLS (and tunneled HTTP) messages. > you're also trusting that the client's response parser doesn't have a vulnerability (and not, say, ignoring some "missing closing bracket" or something) You don't. Authentication 101 (which also applies to how TLS works), authenticity is always validated before inspecting or interacting with content. Same rules that TLS needs to follow when it authenticates its own messages. Furthermore, TLS does nothing to protect you against a server delivering malicious files (e.g., a rogue maintainer or mirror intentionally giving you borked files). > you're also trusting that the client is parsing the correct signature (and not, say, some other signature that was tacked-on later) You don't, as the signature must be authentic from a trusted author (the specific maintainer of the specific package for example). The server or attacker is unable to craft valid signatures, so something "tacked-on" just gets rejected as invalid - just like if you mess with a TLS message. > It's trivially easy to disassemble software to find vulnerabilities like those, though. So it's a lot of trust given for an untrusted software stack. The basis of your trust is invalid and misplaced: Not only is TLS not providing additional security here, TLS is the more complex, fragile and historically vulnerable beast. The only non-privacy risk of using non-TLS mirrors is that a MITM could keep serving you an old version of all your mirrors (which is valid and signed by the maintainers), withholding an update without you knowing. But, such MITM can also just fail your connection to a TLS mirror and then you also can't update, so no: it's just privacy.
• yrro 8mo ago
  Doesn't this break CRL fetching and OCSP queries?
  • Avamander 8mo ago
    Nothing really cares except like Prusa Connect.