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I'm honestly surprised that people still bother with multi-user access control. Defense in depth only works if the defenses are actually manned, and it's been p

I'm honestly surprised that people still bother with multi-user access control. Defense in depth only works if the defenses are actually manned, and it's been pretty clear that nobody's been taking linux local escalation seriously for a very long time. Shared-hosting is, in practice, a high-trust environment, and trying to patch your way around that sounds like the snakeoil logic of Windows security products.

nisa 9y ago
Shared hosting is high trust? You are basically one stolen credit card and 5 minutes away from giving strangers SSH access to a host with lot's of customers that often process sensitive data. Might be true that it's not that important for the cloud crowd where you just use an instance for everything but that that's expensive and not the reality outside of certain bubbles and in the end the problem is just invible to you because Google or Amazon are tightening their hypervisors for you. Lot's of Hadoop/HPC clusters or university desktops depend on this stuff. With everyone moving to Docker and Containers the kernel is the only thing that prevents an intruder from owning the host or the cluster - it's a shame that this is not taken seriously - however they still assign CVEs for it. On a modern cluster node you have software defined networking - having root on a node also means access to different VLANs and stuff like that - most distribued applications just blindly trust anything inside their internal network are a pain the secure (try setting up Hadoop with Kerberos, it's not exactly click&play). A normal setup gives you a SSH key and instant shell on every machine in the cluster. Also most machines are identical so if you own one, you most probably have the means to own all. You can also get all the configuration management data as root. It's for sure not a barrier you should use as your last stand but it's something that should be as hard as possible to overcome. Just giving up and saying who cares only makes the job for future intruders easier.

nisa 9y ago

Shared hosting is high trust? You are basically one stolen credit card and 5 minutes away from giving strangers SSH access to a host with lot's of customers that often process sensitive data. Might be true that it's not that important for the cloud crowd where you just use an instance for everything but that that's expensive and not the reality outside of certain bubbles and in the end the problem is just invible to you because Google or Amazon are tightening their hypervisors for you. Lot's of Hadoop/HPC clusters or university desktops depend on this stuff. With everyone moving to Docker and Containers the kernel is the only thing that prevents an intruder from owning the host or the cluster - it's a shame that this is not taken seriously - however they still assign CVEs for it. On a modern cluster node you have software defined networking - having root on a node also means access to different VLANs and stuff like that - most distribued applications just blindly trust anything inside their internal network are a pain the secure (try setting up Hadoop with Kerberos, it's not exactly click&play). A normal setup gives you a SSH key and instant shell on every machine in the cluster. Also most machines are identical so if you own one, you most probably have the means to own all. You can also get all the configuration management data as root. It's for sure not a barrier you should use as your last stand but it's something that should be as hard as possible to overcome. Just giving up and saying who cares only makes the job for future intruders easier.