USN-3632-1: Linux kernel (Azure) vulnerabilities

24 April 2018

linux-azure vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 16.04 LTS

Summary

Several security issues were fixed in the Linux kernel.

Software Description

  • linux-azure - Linux kernel for Microsoft Azure Cloud systems

Details

It was discovered that a race condition leading to a use-after-free vulnerability existed in the ALSA PCM subsystem of the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2017-0861)

It was discovered that the KVM implementation in the Linux kernel allowed passthrough of the diagnostic I/O port 0x80. An attacker in a guest VM could use this to cause a denial of service (system crash) in the host OS. (CVE-2017-1000407)

It was discovered that a use-after-free vulnerability existed in the network namespaces 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-2017-15129)

It was discovered that the HugeTLB component of the Linux kernel did not properly handle holes in hugetlb ranges. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2017-16994)

It was discovered that the netfilter component of the Linux did not properly restrict access to the connection tracking helpers list. A local attacker could use this to bypass intended access restrictions. (CVE-2017-17448)

It was discovered that the netfilter passive OS fingerprinting (xt_osf) module did not properly perform access control checks. A local attacker could improperly modify the system-wide OS fingerprint list. (CVE-2017-17450)

Dmitry Vyukov discovered that the KVM implementation in the Linux kernel contained an out-of-bounds read when handling memory-mapped I/O. A local attacker could use this to expose sensitive information. (CVE-2017-17741)

It was discovered that the Salsa20 encryption algorithm implementations in the Linux kernel did not properly handle zero-length inputs. A local attacker could use this to cause a denial of service (system crash). (CVE-2017-17805)

It was discovered that the HMAC implementation did not validate the state of the underlying cryptographic hash algorithm. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2017-17806)

It was discovered that the keyring implementation in the Linux kernel did not properly check permissions when a key request was performed on a task’s default keyring. A local attacker could use this to add keys to unauthorized keyrings. (CVE-2017-17807)

It was discovered that the Broadcom NetXtremeII ethernet driver in the Linux kernel did not properly validate Generic Segment Offload (GSO) packet sizes. An attacker could use this to cause a denial of service (interface unavailability). (CVE-2018-1000026)

It was discovered that the Reliable Datagram Socket (RDS) implementation in the Linux kernel contained an out-of-bounds write during RDMA page allocation. An attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-5332)

Mohamed Ghannam discovered a null pointer dereference in the RDS (Reliable Datagram Sockets) protocol implementation of the Linux kernel. A local attacker could use this to cause a denial of service (system crash). (CVE-2018-5333)

范龙飞 discovered that a race condition existed in loop block device 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-2018-5344)

It was discovered that the Broadcom UniMAC MDIO bus controller driver in the Linux kernel did not properly validate device resources. A local attacker could use this to cause a denial of service (system crash). (CVE-2018-8043)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 16.04 LTS
linux-image-4.13.0-1014-azure - 4.13.0-1014.17
linux-image-azure - 4.13.0.1014.16

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

After a standard system update you need to reboot your computer to make all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual, linux-powerpc), a standard system upgrade will automatically perform this as well.

References