ISOMAN

CVE

CVE-2018-13405

The inode_init_owner function in fs/inode.c in the Linux kernel through 3.16 allows local users to create files with an unintended group ownership, in a scenario where a directory is SGID to a certain group and is writable by a user who is not a member of that group. Here, the non-member can trigger creation of a plain file whose group ownership is that group. The intended behavior was that the non-member can trigger creation of a directory (but not a plain file) whose group ownership is that group. The non-member can escalate privileges by making the plain file executable and SGID.

Severity
HIGH
CVSS
7.8
Published
Modified

Linked Releases

References

  1. http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=0fa3ecd87848c9c93c2c828ef4c3a8ca36ce46c7
  2. http://openwall.com/lists/oss-security/2018/07/13/2
  3. http://www.securityfocus.com/bid/106503
  4. https://access.redhat.com/errata/RHSA-2018:2948
  5. https://access.redhat.com/errata/RHSA-2018:3083
  6. https://access.redhat.com/errata/RHSA-2018:3096
  7. https://access.redhat.com/errata/RHSA-2019:0717
  8. https://access.redhat.com/errata/RHSA-2019:2476
  9. https://access.redhat.com/errata/RHSA-2019:2566
  10. https://access.redhat.com/errata/RHSA-2019:2696
  11. https://access.redhat.com/errata/RHSA-2019:2730
  12. https://access.redhat.com/errata/RHSA-2019:4159
  13. https://access.redhat.com/errata/RHSA-2019:4164
  14. https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=0b3369840cd61c23e2b9241093737b4c395cb406
  15. https://github.com/torvalds/linux/commit/0fa3ecd87848c9c93c2c828ef4c3a8ca36ce46c7
  16. https://lists.debian.org/debian-lts-announce/2018/08/msg00014.html
  17. https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HRBNBX73SAFKQWBOX76SLMWPTKJPVGEJ/
  18. https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MTKKIAUMR5FAYLZ7HLEPOXMKAAE3BYBQ/
  19. https://support.f5.com/csp/article/K00854051
  20. https://twitter.com/grsecurity/status/1015082951204327425