1. Ubuntu Security Notices
  2. USN-2759-1

USN-2759-1: Linux kernel vulnerabilities

Publication date

1 October 2015

Overview

Several security issues were fixed in the kernel.

Releases

Packages

Details

It was discovered that an integer overflow error existed in the SCSI
generic (sg) driver in the Linux kernel. A local attacker with write
permission to a SCSI generic device could use this to cause a denial of
service (system crash) or potentially escalate their privileges.
(CVE-2015-5707)

Marc-André Lureau discovered that the vhost driver did not properly
release the userspace provided log file descriptor. A privileged attacker
could use this to cause a denial of service (resource exhaustion).
(CVE-2015-6252)

It was discovered that the Linux kernel’s perf subsystem did not bound
callchain backtraces on PowerPC 64. A local attacker could use this to
cause a denial of service. (CVE-2015-6526)

It was discovered that an integer overflow error existed in the SCSI
generic (sg) driver in the Linux kernel. A local attacker with write
permission to a SCSI generic device could use this to cause a denial of
service (system crash) or potentially escalate their privileges.
(CVE-2015-5707)

Marc-André Lureau discovered that the vhost driver did not properly
release the userspace provided log file descriptor. A privileged attacker
could use this to cause a denial of service (resource exhaustion).
(CVE-2015-6252)

It was discovered that the Linux kernel’s perf subsystem did not bound
callchain backtraces on PowerPC 64. A local attacker could use this to
cause a denial of service. (CVE-2015-6526)

Update instructions

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

Learn more about how to get the fixes.

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. If you use linux-restricted-modules, you have to update that package as well to get modules which work with the new kernel version. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-server, linux-powerpc), a standard system upgrade will automatically perform this as well.

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

Ubuntu Release Package Version
12.04 precise linux-image-3.2.0-91-generic-pae –  3.2.0-91.129
linux-image-3.2.0-91-powerpc64-smp –  3.2.0-91.129
linux-image-3.2.0-91-generic –  3.2.0-91.129
linux-image-3.2.0-91-virtual –  3.2.0-91.129
linux-image-3.2.0-91-omap –  3.2.0-91.129
linux-image-3.2.0-91-powerpc-smp –  3.2.0-91.129
linux-image-3.2.0-91-highbank –  3.2.0-91.129

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References

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