USN-3405-1: Linux kernel vulnerabilities

It was discovered that a use-after-free vulnerability existed in the POSIX message queue implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2017-11176) Huang Weller discovered that the ext4 filesystem implementation in the Linux kernel mishandled a needs-flushing-before-commit list. A local attacker could use this to expose sensitive information. (CVE-2017-7495) It was discovered that a buffer overflow existed in the Broadcom FullMAC WLAN driver in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2017-7541) It was discovered that the Linux kernel did not honor the UEFI secure boot mode when performing a kexec operation. A local attacker could use this to bypass secure boot restrictions. (CVE-2015-7837)