CVE-2018-14678

Published: 28 July 2018

An issue was discovered in the Linux kernel through 4.17.11, as used in Xen through 4.11.x. The xen_failsafe_callback entry point in arch/x86/entry/entry_64.S does not properly maintain RBX, which allows local users to cause a denial of service (uninitialized memory usage and system crash). Within Xen, 64-bit x86 PV Linux guest OS users can trigger a guest OS crash or possibly gain privileges.

From the Ubuntu security team

M. Vefa Bicakci and Andy Lutomirski discovered that the kernel did not properly set up all arguments to an error handler callback used when running as a paravirtualized guest. An unprivileged attacker in a paravirtualized guest VM could use this to cause a denial of service (guest VM crash).

Priority

Medium

CVSS 3 base score: 7.8

Status

References

• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-14678
• https://xenbits.xen.org/xsa/advisory-274.html
• https://git.kernel.org/linus/b3681dd548d06deb2e1573890829dff4b15abf46
• https://ubuntu.com/security/notices/USN-3931-1
• https://ubuntu.com/security/notices/USN-3931-2
• NVD
• Launchpad
• Debian