7 ms·

Beware of hacked ISOs if you downloaded Linux Mint on February 20th

171 points by ty___ler 11y ago

StavrosK 11y ago
What other ways are there to download, apart from http and torrents?
- khedoros 11y ago
  FTP?
  - stock_toaster 11y ago
    maybe IRC and NNTP too.
  - StavrosK 11y ago
    I mean "what other ways do they have to download this?" All I saw is HTTP and Torrent, so I'm curious as to what exactly got compromised.
- praeivis 11y ago
  torrents cant get compromised so you are safe if downloaded via torrents.
cdevs 11y ago
Does anyone know the start date ? I had a friend install it for their laptop two weeks ago
- detaro 11y ago
  >We were exposed to an intrusion today. > [...] >Finally, the situation both happened and was solved today, so it should only impact people who downloaded this edition on February 20th.
i_have_to_speak 11y ago
Looks like something is going on again. Their website is down currently. [21-Feb 02:55 UTC]
- corvus_sapiens 11y ago
  "Edit by Clem: We shut down the server until we find the source of the second intrusion (probably something left by the first)." http://blog.linuxmint.com/?p=2994 http://blog.linuxmint.com/?p=2994
jtchang 11y ago
Well that is scary. I personally don't check ISO checksums and signatures very often. Probably the only time I do is when I sometimes get install errors and wonder if I got all the bits and if anything got corrupted.
- detaro 11y ago
  If they managed to hack the site to point to the new iso, they probably also changed any checksums. Signatures help, if you have a way to verify that you are using the right key.
- RaleyField 11y ago
  > don't check ISO checksums I've grown obsessive about it. When you're conscious about that it's amazing (to put mildly) how many prominent projects don't bother with any authentication.
mcpherrinm 11y ago
I am pretty sad they're posting MD5 sums of the correct images: It's pretty trivial to collide MD5 -- and when you've got an active attacker, this is something you should worry about. SHA1/2 at least, but preferably a gpg signature would be much better.
- ryanlol 11y ago
  >It's pretty trivial to collide MD5 ... collisions=/=second-preimage attacks >SHA1/2 at least, but preferably a gpg signature would be much better. SHA1/2 isn't any better, you're never going to get hit by file corruption that magically also is a md5 collision.
  - KMag 11y ago
    I think I understand you, but I think you could be a bit more explicit in your assertion. I think you're saying MD5 is still a decent checksum for non-cryptographic purposes. Without a cryptographic signature or other authenticated integrity-checked distribution channel, there's very little advantage of using a cryptographic checksum.
    - 0xcde4c3db 11y ago
      The relevant thing here is that the main weakness in MD5 requires both the "good" and "evil" versions of the message (or file) to be produced by the same party. It doesn't allow J. Random Attacker to swoop in and alter things that already exist. However, it would allow a hypothetical Evil Maintainer to pre-cook "good" and "evil" versions and swap between them without changing the MD5.
  - _jomo 11y ago
    How do you get hit by file corruption when downloading via TCP in 2016? I don't recall this ever happening to me.
    - ryanlol 11y ago
      While possible, it's really really unlikely for this to happen without some fairly serious network issues between you and whoever you're downloading from.
ryanlol 11y ago
I'll just leave this here forums.linuxmint.com pwd /root/hacked_distros/mint/var/www/forums.linuxmint.com forums.linuxmint.com cat config.php <?php // phpBB 3.0.x auto-generated configuration file // Do not change anything in this file! $dbms = 'mysql'; $dbhost = 'localhost'; $dbport = ''; $dbname = 'lms14'; $dbuser = 'lms14'; $dbpasswd = 'upMint'; Perhaps the insanely secure db credentials had something to do with the breach? But what would I know.
- hackuser 11y ago
  You have an excellent point, but there's no reason to help attackers by giving them the credentials.
  - majewsky 11y ago
    Indeed. Instead of `cat`, OP could've used `sha256sum` on the config.php to prove the authenticity of your report without exposing the site to even more attacks.
    - ryanlol 11y ago
      But that wasn't the point, the point was to expose the level of stupidity at play here. I strongly believe the users deserve to know just how incompetent these guys are, because next time it won't be some idiot swapping the iso links. It'll be someone slightly more competent that pushes a backdoored commit or gets into the apt repos, and then _every_ _single_ user will be affected... Also, at the time of the posting the site was down. And it remains so.
- cmurf 11y ago
  Might not hurt to post this in the comments section of the Mint blog.
  - orionblastar 11y ago
    If they used the same password on the forums and blog then they still have a problem. They need to be notified of this and change the password to a more secure one. The config.php file should not be readable by an anonymous user, that is a security risk.
anishathalye 11y ago
It's somewhat disappointing that this blog article is served over HTTP, and it's impossible to access it via HTTPS. How do we know that these new MD5s are to be trusted?
- bogus- 11y ago
  Linux Mint doesn't seem to prioritize security in general. No TLS for ISOs, no easily spottable signatures for ISOs, marking security updates untrusted by default...
  - RaleyField 11y ago
    They also ignore (at least they used to) DNS servers from DHCP and use Google's public DNS servers completely oblivious of why users might not want this.
btrask 11y ago
I was trying to download Linux securely a month or so ago. It's actually embarrassingly difficult to do. The only two distros that did it right (that I could find) are Debian and Alpine Linux. The rest (including Mint and Ubuntu) had hashes (usually MD5) or GPG keys served over HTTP.
- chei0aiV 11y ago
  If you can think of any improvements Debian could make, please do suggest them via bug reports or on the mailing list. If you would like to work on fixing some of our issues, here are the ones we know about: https://wiki.debian.org/Hardening/RepoAndImages https://wiki.debian.org/Hardening/RepoAndImages
  - btrask 11y ago
    Debian is already outstanding in this regard (and others)! One minor suggestion would be to provide ISO hashes over HTTPS. It's just as secure as using GPG with fingerprints sent over HTTPS, and it's a lot easier. The fingerprints (https://www.debian.org/CD/verify https://www.debian.org/CD/verify) could also be made more prominent (perhaps put on the main download page). Thanks again!
  - kbaker 11y ago
    Maybe in a GPG-signed release email add magnet URLs for the official torrents. This is kind of in 'No magnet: links for bittorrent downloads on SSL'
- bcl 11y ago
  Fedora publishes GPG signed SHA256's of the iso's. eg. https://dl.fedoraproject.org/pub/fedora/linux/releases/23/Workstation/x86_64/iso/Fedora-Workstation-23-x86_64-CHECKSUM https://dl.fedoraproject.org/pub/fedora/linux/releases/23/Wo...
  - btrask 11y ago
    Thanks! Fedora was one I didn't try (to install; I use it all the time). However there's still no way to use RPMFusion: http://rpmfusion.org/keys http://rpmfusion.org/keys Maybe there's something I'm missing?
dghughes 11y ago
Now you tell me.

171 points by ty___ler 11y ago

StavrosK 11y ago

What other ways are there to download, apart from http and torrents?

khedoros 11y ago
FTP?
- stock_toaster 11y ago
  maybe IRC and NNTP too.
- StavrosK 11y ago
  I mean "what other ways do they have to download this?" All I saw is HTTP and Torrent, so I'm curious as to what exactly got compromised.
praeivis 11y ago
torrents cant get compromised so you are safe if downloaded via torrents.

cdevs 11y ago

Does anyone know the start date ? I had a friend install it for their laptop two weeks ago

detaro 11y ago
>We were exposed to an intrusion today. > [...] >Finally, the situation both happened and was solved today, so it should only impact people who downloaded this edition on February 20th.

i_have_to_speak 11y ago

Looks like something is going on again. Their website is down currently. [21-Feb 02:55 UTC]

corvus_sapiens 11y ago
"Edit by Clem: We shut down the server until we find the source of the second intrusion (probably something left by the first)." http://blog.linuxmint.com/?p=2994 http://blog.linuxmint.com/?p=2994

jtchang 11y ago

Well that is scary. I personally don't check ISO checksums and signatures very often. Probably the only time I do is when I sometimes get install errors and wonder if I got all the bits and if anything got corrupted.

detaro 11y ago
If they managed to hack the site to point to the new iso, they probably also changed any checksums. Signatures help, if you have a way to verify that you are using the right key.
RaleyField 11y ago
> don't check ISO checksums I've grown obsessive about it. When you're conscious about that it's amazing (to put mildly) how many prominent projects don't bother with any authentication.

mcpherrinm 11y ago

I am pretty sad they're posting MD5 sums of the correct images: It's pretty trivial to collide MD5 -- and when you've got an active attacker, this is something you should worry about. SHA1/2 at least, but preferably a gpg signature would be much better.

ryanlol 11y ago
>It's pretty trivial to collide MD5 ... collisions=/=second-preimage attacks >SHA1/2 at least, but preferably a gpg signature would be much better. SHA1/2 isn't any better, you're never going to get hit by file corruption that magically also is a md5 collision.
- KMag 11y ago
  I think I understand you, but I think you could be a bit more explicit in your assertion. I think you're saying MD5 is still a decent checksum for non-cryptographic purposes. Without a cryptographic signature or other authenticated integrity-checked distribution channel, there's very little advantage of using a cryptographic checksum.
  - 0xcde4c3db 11y ago
    The relevant thing here is that the main weakness in MD5 requires both the "good" and "evil" versions of the message (or file) to be produced by the same party. It doesn't allow J. Random Attacker to swoop in and alter things that already exist. However, it would allow a hypothetical Evil Maintainer to pre-cook "good" and "evil" versions and swap between them without changing the MD5.
- _jomo 11y ago
  How do you get hit by file corruption when downloading via TCP in 2016? I don't recall this ever happening to me.
  - ryanlol 11y ago
    While possible, it's really really unlikely for this to happen without some fairly serious network issues between you and whoever you're downloading from.

ryanlol 11y ago

I'll just leave this here forums.linuxmint.com pwd /root/hacked_distros/mint/var/www/forums.linuxmint.com forums.linuxmint.com cat config.php <?php // phpBB 3.0.x auto-generated configuration file // Do not change anything in this file! $dbms = 'mysql'; $dbhost = 'localhost'; $dbport = ''; $dbname = 'lms14'; $dbuser = 'lms14'; $dbpasswd = 'upMint'; Perhaps the insanely secure db credentials had something to do with the breach? But what would I know.

hackuser 11y ago
You have an excellent point, but there's no reason to help attackers by giving them the credentials.
- majewsky 11y ago
  Indeed. Instead of `cat`, OP could've used `sha256sum` on the config.php to prove the authenticity of your report without exposing the site to even more attacks.
  - ryanlol 11y ago
    But that wasn't the point, the point was to expose the level of stupidity at play here. I strongly believe the users deserve to know just how incompetent these guys are, because next time it won't be some idiot swapping the iso links. It'll be someone slightly more competent that pushes a backdoored commit or gets into the apt repos, and then _every_ _single_ user will be affected... Also, at the time of the posting the site was down. And it remains so.
cmurf 11y ago
Might not hurt to post this in the comments section of the Mint blog.
- orionblastar 11y ago
  If they used the same password on the forums and blog then they still have a problem. They need to be notified of this and change the password to a more secure one. The config.php file should not be readable by an anonymous user, that is a security risk.

anishathalye 11y ago

It's somewhat disappointing that this blog article is served over HTTP, and it's impossible to access it via HTTPS. How do we know that these new MD5s are to be trusted?

bogus- 11y ago
Linux Mint doesn't seem to prioritize security in general. No TLS for ISOs, no easily spottable signatures for ISOs, marking security updates untrusted by default...
- RaleyField 11y ago
  They also ignore (at least they used to) DNS servers from DHCP and use Google's public DNS servers completely oblivious of why users might not want this.

btrask 11y ago

I was trying to download Linux securely a month or so ago. It's actually embarrassingly difficult to do. The only two distros that did it right (that I could find) are Debian and Alpine Linux. The rest (including Mint and Ubuntu) had hashes (usually MD5) or GPG keys served over HTTP.

chei0aiV 11y ago
If you can think of any improvements Debian could make, please do suggest them via bug reports or on the mailing list. If you would like to work on fixing some of our issues, here are the ones we know about: https://wiki.debian.org/Hardening/RepoAndImages https://wiki.debian.org/Hardening/RepoAndImages
- btrask 11y ago
  Debian is already outstanding in this regard (and others)! One minor suggestion would be to provide ISO hashes over HTTPS. It's just as secure as using GPG with fingerprints sent over HTTPS, and it's a lot easier. The fingerprints (https://www.debian.org/CD/verify https://www.debian.org/CD/verify) could also be made more prominent (perhaps put on the main download page). Thanks again!
- kbaker 11y ago
  Maybe in a GPG-signed release email add magnet URLs for the official torrents. This is kind of in 'No magnet: links for bittorrent downloads on SSL'
bcl 11y ago
Fedora publishes GPG signed SHA256's of the iso's. eg. https://dl.fedoraproject.org/pub/fedora/linux/releases/23/Workstation/x86_64/iso/Fedora-Workstation-23-x86_64-CHECKSUM https://dl.fedoraproject.org/pub/fedora/linux/releases/23/Wo...
- btrask 11y ago
  Thanks! Fedora was one I didn't try (to install; I use it all the time). However there's still no way to use RPMFusion: http://rpmfusion.org/keys http://rpmfusion.org/keys Maybe there's something I'm missing?

dghughes 11y ago

Now you tell me.