6 ms·
This is a pedantry for the sake of it. If it's present by default and an attacker can trivially cause it to be loaded, it's the same as "on by default".
by chromacity 4mo ago
This is a pedantry for the sake of it. If it's present by default and an attacker can trivially cause it to be loaded, it's the same as "on by default".
- akerl_ 4mo agoIt’s radically different than on by default. Having a service that automatically starts and listens on the network is radically different from having a module that a local administrator can load. If you want to block module loads, you’re one sysctl flag away.
- zzrrt 4mo ago> having a module that a local administrator can load This is a successful local privilege escalation, so local administrator privs were not needed. In default configuration of all distros, apparently. > If you want to block module loads, you’re one sysctl flag away. The modules aren't really the point, it's that unnecessary features (to 99% of us?) were accessible by default without privs.
- zbentley 4mo agoThis is "a service that automatically starts". That's what automatic kernel module loading is for! It's not any different from putting an always-running network service behind socket activation instead. The security boundary/risk is nearly identical between the two.
- akerl_ 4mo agoOne is remotely accessible. The other is locally accessible.
- zbentley 4mo agoThe GP you were replying to mentioned a vulnerability "present by default and an attacker can trivially cause it to be loaded". You responded contrasting a network service with an administrator-loadable module. This is neither of those. It's an LPE, not a remote exploit. It doesn't require an administrator (root) to load anything. In context of this vuln, it's exactly analogous to socket activation. The scope of an LPE vuln is local; yes. What does that have to do with the rest of your comments?
- akerl_ 4mo agoI don't understand what point you're trying to make here. I originally replied to a comment saying "This feels like the practice of Linux distros back in 1999 when they'd ship default installs with dozens of network services exposed to the internet". It is not like that.
- Sohcahtoa82 4mo ago> This is a pedantry for the sake of it. Par for the course for HN.
- thayne 4mo agoHow would the attacker cause one of these modules to get loaded without already having root?
- staticassertion 4mo agoTrivially. Kernel modules autoload through various unprivileged mechanisms.
- deleted 4mo ago[deleted]