4 ms·

TL;DR: High Sierra was released with a broken kill system call. It can sometimes cause a kernel panic. Apparently Apple doesn't think this is a security issue:

by rdtsc 9y ago

TL;DR: High Sierra was released with a broken kill system call. It can sometimes cause a kernel panic. Apparently Apple doesn't think this is a security issue: https://groups.google.com/forum/m/#!topic/nix-devel/KV9eomIdxWE https://groups.google.com/forum/m/#!topic/nix-devel/KV9eomId... Unprivileged users being able to panic the kernel would seem to be security related, but I am just an amateur.

lstyls 9y ago
Unless it has a clear exploit it makes some amount of sense to me that this would not be put on a security timeline. But I am not a security expert either. There was an anecdote in the issue tracker that suggested there was some level of privilege escalation but that did not contain a repro or any supporting evidence.
- Khaine 9y ago
  IT Security is usually considered through the prism of the CIA Triad[1]. Confidentiality, Integrity and Availability. Therefore any issue which impacts the availability of a service or device is a security issue. [1] https://en.wikipedia.org/wiki/Information_security#Key_concepts https://en.wikipedia.org/wiki/Information_security#Key_conce...
  - AlphaSite 9y ago
    This is availability of a single system, not a distributed system.
    - Khaine 9y ago
      Its the same concept. If a user can't use his computer because of a local DoS its still a security issue. To make this really simple, imagine if I ran a fork bomb on one server. That makes the server unavailable for users who want to log into it for whatever reason. Therefore it is a security issue. It doesn't matter if its an end user device, one sever or a distributed system. I as the user cannot do what I want to do. That is what 'availability' means in the CIA triad.
      - lstyls 9y ago
        I get why it's a security issue. My point is that it's not on the same level as a critical vulnerability.
revelation 9y ago
Well, nobody uses MacOS seriously, so unprivileged DoS and the ensuing data loss is clearly not a security issue.
floatingatoll 9y ago
Incorrect. Unprivileged users with local system access and the ability to send kill signals to arbitrary process IDs. Not “unprivileged users” alone.
- bzbarsky 9y ago
  > with local system access The discussion linked from the github issue sounds like "kill SIGKILL -1" at a shell prompt is enough to trigger the issue. That just requires a shell, not local system access. > and the ability to send kill signals to arbitrary process IDs This is precisely the part that is _not_ required but should be.

by rdtsc 9y ago

lstyls 9y ago

Unless it has a clear exploit it makes some amount of sense to me that this would not be put on a security timeline. But I am not a security expert either. There was an anecdote in the issue tracker that suggested there was some level of privilege escalation but that did not contain a repro or any supporting evidence.

Khaine 9y ago
IT Security is usually considered through the prism of the CIA Triad[1]. Confidentiality, Integrity and Availability. Therefore any issue which impacts the availability of a service or device is a security issue. [1] https://en.wikipedia.org/wiki/Information_security#Key_concepts https://en.wikipedia.org/wiki/Information_security#Key_conce...
- AlphaSite 9y ago
  This is availability of a single system, not a distributed system.
  - Khaine 9y ago
    Its the same concept. If a user can't use his computer because of a local DoS its still a security issue. To make this really simple, imagine if I ran a fork bomb on one server. That makes the server unavailable for users who want to log into it for whatever reason. Therefore it is a security issue. It doesn't matter if its an end user device, one sever or a distributed system. I as the user cannot do what I want to do. That is what 'availability' means in the CIA triad.
    - lstyls 9y ago
      I get why it's a security issue. My point is that it's not on the same level as a critical vulnerability.

revelation 9y ago

Well, nobody uses MacOS seriously, so unprivileged DoS and the ensuing data loss is clearly not a security issue.

floatingatoll 9y ago

Incorrect. Unprivileged users with local system access and the ability to send kill signals to arbitrary process IDs. Not “unprivileged users” alone.

bzbarsky 9y ago
> with local system access The discussion linked from the github issue sounds like "kill SIGKILL -1" at a shell prompt is enough to trigger the issue. That just requires a shell, not local system access. > and the ability to send kill signals to arbitrary process IDs This is precisely the part that is _not_ required but should be.