USN-2965-2: Linux kernel (Xenial HWE) vulnerabilities

6 May 2016

linux-lts-xenial vulnerabilities

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

  • Ubuntu 14.04 LTS

Summary

Several security issues were fixed in the kernel.

Software Description

  • linux-lts-xenial - Linux hardware enablement kernel from Xenial for Trusty

Details

USN-2965-1 fixed vulnerabilities in the Linux kernel for Ubuntu 16.04 LTS. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu 14.04 LTS.

Jann Horn discovered that the extended Berkeley Packet Filter (eBPF) implementation in the Linux kernel did not properly reference count file descriptors, leading to a use-after-free. A local unprivileged attacker could use this to gain administrative privileges. (CVE-2016-4557)

Ralf Spenneberg discovered that the USB sound subsystem in the Linux kernel did not properly validate USB device descriptors. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-2184)

Ralf Spenneberg discovered that the ATI Wonder Remote II USB driver in the Linux kernel did not properly validate USB device descriptors. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-2185)

Ralf Spenneberg discovered that the PowerMate USB driver in the Linux kernel did not properly validate USB device descriptors. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-2186)

Ralf Spenneberg discovered that the I/O-Warrior USB device driver in the Linux kernel did not properly validate USB device descriptors. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-2188)

It was discovered that the Linux kernel did not enforce limits on the amount of data allocated to buffer pipes. A local attacker could use this to cause a denial of service (resource exhaustion). (CVE-2016-2847)

Sergej Schumilo, Hendrik Schwartke, and Ralf Spenneberg discovered that the MCT USB RS232 Converter device driver in the Linux kernel did not properly validate USB device descriptors. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-3136)

Sergej Schumilo, Hendrik Schwartke, and Ralf Spenneberg discovered that the Cypress M8 USB device driver in the Linux kernel did not properly validate USB device descriptors. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-3137)

Sergej Schumilo, Hendrik Schwartke, and Ralf Spenneberg discovered that the USB abstract device control driver for modems and ISDN adapters did not validate endpoint descriptors. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-3138)

Sergej Schumilo, Hendrik Schwartke, and Ralf Spenneberg discovered that the Linux kernel’s USB driver for Digi AccelePort serial converters did not properly validate USB device descriptors. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-3140)

It was discovered that the IPv4 implementation in the Linux kernel did not perform the destruction of inet device objects properly. An attacker in a guest OS could use this to cause a denial of service (networking outage) in the host OS. (CVE-2016-3156)

Andy Lutomirski discovered that the Linux kernel did not properly context- switch IOPL on 64-bit PV Xen guests. An attacker in a guest OS could use this to cause a denial of service (guest OS crash), gain privileges, or obtain sensitive information. (CVE-2016-3157)

Hector Marco and Ismael Ripoll discovered that the Linux kernel would improperly disable Address Space Layout Randomization (ASLR) for x86 processes running in 32 bit mode if stack-consumption resource limits were disabled. A local attacker could use this to make it easier to exploit an existing vulnerability in a setuid/setgid program. (CVE-2016-3672)

It was discovered that the Linux kernel’s USB driver for IMS Passenger Control Unit devices did not properly validate the device’s interfaces. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-3689)

Andrey Konovalov discovered that the CDC Network Control Model USB driver in the Linux kernel did not cancel work events queued if a later error occurred, resulting in a use-after-free. An attacker with physical access could use this to cause a denial of service (system crash). (CVE-2016-3951)

It was discovered that an out-of-bounds write could occur when handling incoming packets in the USB/IP implementation in the Linux kernel. A remote attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2016-3955)

Update instructions

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

Ubuntu 14.04 LTS
linux-image-4.4.0-22-generic - 4.4.0-22.39~14.04.1
linux-image-4.4.0-22-generic-lpae - 4.4.0-22.39~14.04.1
linux-image-4.4.0-22-lowlatency - 4.4.0-22.39~14.04.1
linux-image-4.4.0-22-powerpc-e500mc - 4.4.0-22.39~14.04.1
linux-image-4.4.0-22-powerpc-smp - 4.4.0-22.39~14.04.1
linux-image-4.4.0-22-powerpc64-emb - 4.4.0-22.39~14.04.1
linux-image-4.4.0-22-powerpc64-smp - 4.4.0-22.39~14.04.1

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