Description

The keyctl_read_key function in security/keys/keyctl.c in the Linux kernel before 4.3.4 does not properly use a semaphore, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a crafted application that leverages a race condition between keyctl_revoke and keyctl_read calls.

References

http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b4a1b4f5047e4f54e194681125c74c0aa64d637d

http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00094.html

http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00045.html

http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00038.html

http://www.debian.org/security/2016/dsa-3434

http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.3.4

http://www.securityfocus.com/bid/79903

http://www.ubuntu.com/usn/USN-2888-1

http://www.ubuntu.com/usn/USN-2890-1

http://www.ubuntu.com/usn/USN-2890-2

http://www.ubuntu.com/usn/USN-2890-3

http://www.ubuntu.com/usn/USN-2911-1

http://www.ubuntu.com/usn/USN-2911-2

https://bugzilla.redhat.com/show_bug.cgi?id=1291197

https://github.com/torvalds/linux/commit/b4a1b4f5047e4f54e194681125c74c0aa64d637d

https://security-tracker.debian.org/tracker/CVE-2015-7550

Details

Risk Information

CVSS v2

CVSS v3