The KEYS subsystem in the Linux kernel omitted an access-control check when adding a key to the current task's "default request-key keyring" via the request_key() system call, allowing a local user to use a sequence of crafted system calls to add keys to a keyring with only Search permission (not Write permission) to that keyring, related to construct_get_dest_keyring() in security/keys/request_key.c. Upstream patch: https://github.com/torvalds/linux/commit/4dca6ea1d9432052afb06baf2e3ae78188a4410b
Created kernel tracking bugs for this issue: Affects: fedora-all [bug 1528337]
This was fixed for Fedora with the 4.14.6 stable updates.
Statement: This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 5. This is not currently planned to be addressed in future updates of the product due to its life cycle. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/. This issue affects the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 6, 7, its real-time kernel, Red Hat Enterprise MRG 2, Red Hat Enterprise Linux 7 for ARM 64 and Red Hat Enterprise Linux 7 for Power 9 LE. Future Linux kernel updates for the respective releases may address this issue.
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2020:1016 https://access.redhat.com/errata/RHSA-2020:1016
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2020:1070 https://access.redhat.com/errata/RHSA-2020:1070
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2017-17807