Debian Security Advisory

DLA-993-2 linux -- LTS security update

Date Reported:
27 Jun 2017
Affected Packages:
linux
Vulnerable:
Yes
Security database references:
In the Debian bugtracking system: Bug 865303.
More information:

The security update announced as DLA-993-1 caused regressions for some applications using Java - including jsvc, LibreOffice and Scilab - due to the fix for CVE-2017-1000364. Updated packages are now available to correct this issue. For reference, the relevant part of the original advisory text follows.

  • CVE-2017-1000364

    The Qualys Research Labs discovered that the size of the stack guard page is not sufficiently large. The stack-pointer can jump over the guard-page and moving from the stack into another memory region without accessing the guard-page. In this case no page-fault exception is raised and the stack extends into the other memory region. An attacker can exploit this flaw for privilege escalation.

    The default stack gap protection is set to 256 pages and can be configured via the stack_guard_gap kernel parameter on the kernel command line.

    Further details can be found at https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt

For Debian 7 Wheezy, this problem has been fixed in version 3.2.89-2.

For Debian 8 Jessie, this problem has been fixed in version 3.16.43-2+deb8u2.

For Debian 9 Stretch, this problem has been fixed in version 4.9.30-2+deb9u2.

We recommend that you upgrade your linux packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS