Medium
Canonical Ubuntu
USN-4008-1 fixed multiple security issues in the Linux kernel. This update provides the corresponding changes to AppArmor policy for correctly operating under the Linux kernel with fixes for CVE-2019-11190. Without these changes, some profile transitions may be unintentionally denied due to missing mmap (’m’) rules.
Original advisory details:
Robert Święcki discovered that the Linux kernel did not properly apply Address Space Layout Randomization (ASLR) in some situations for setuid elf binaries. A local attacker could use this to improve the chances of exploiting an existing vulnerability in a setuid elf binary. (CVE-2019-11190)
It was discovered that a null pointer dereference vulnerability existed in the LSI Logic MegaRAID driver in the Linux kernel. A local attacker could use this to cause a denial of service (system crash). (CVE-2019-11810)
It was discovered that a race condition leading to a use-after-free existed in the Reliable Datagram Sockets (RDS) protocol implementation in the Linux kernel. The RDS protocol is blacklisted by default in Ubuntu. If enabled, a local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-11815)
Federico Manuel Bento discovered that the Linux kernel did not properly apply Address Space Layout Randomization (ASLR) in some situations for setuid a.out binaries. A local attacker could use this to improve the chances of exploiting an existing vulnerability in a setuid a.out binary. (CVE-2019-11191)
As a hardening measure, this update disables a.out support.
CVEs contained in this USN include: CVE-2019-11190, CVE-2019-11191, CVE-2019-11810, CVE-2019-11815
Severity is medium unless otherwise noted.
Users of affected products are strongly encouraged to follow one of the mitigations below: