PT-2017-17784 · Linux+5 · Linux Kernel+5

Published 2017-06-23 · Updated 2019-10-09 · CVE-2017-7518

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to 4.12

Description A flaw was found in the way the KVM module processed the trap flag (TF) bit in EFLAGS during emulation of the syscall instruction. This leads to a debug exception (#DB) being raised in the guest stack. A user or process inside a guest could use this flaw to potentially escalate their privileges inside the guest.

Recommendations For Linux kernel versions prior to 4.12, update to version 4.12 or later to resolve the issue. As a temporary workaround, consider restricting access to the KVM module to minimize the risk of exploitation.

Fix

Improper Handling of Exceptional Conditions

Weakness Enumeration

CWE-755

CWE-250

Related Identifiers

ALT-PU-2017-1854

ALT-PU-2017-2424

ALT-PU-2017-2685

ALT-PU-2018-1991

CESA-2018_0395

CVE-2017-7518

DSA-3981-1

MGASA-2017-0381

MGASA-2017-0383

MGASA-2017-0384

MGASA-2017-0463

MGASA-2017-0466

MGASA-2017-0467

MGASA-2018-0062

MGASA-2018-0063

MGASA-2018-0064

OPENSUSE-SU-2017_1825-1

RHSA-2018:0395

RHSA-2018:0412

RHSA-2018_0395

RHSA-2018_0412

SUSE-SU-2017:2869-1

SUSE-SU-2017:2908-1

SUSE-SU-2017:2920-1

SUSE-SU-2017:2956-1

USN-3619-1

USN-3619-2

USN-3754-1

Affected Products

Alt Linux

Centos

Linux Kernel

Red Hat

Suse

Ubuntu

References · 446

• https://ubuntu.com/security/CVE-2017-9984 · Vendor Advisory
• https://ubuntu.com/security/CVE-2017-17806 · Vendor Advisory
• https://osv.dev/vulnerability/MGASA-2018-0064 · Vendor Advisory
• https://ubuntu.com/security/CVE-2018-5333 · Vendor Advisory
• https://usn.ubuntu.com/3619-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2018-13406 · Vendor Advisory
• https://advisories.mageia.org/MGASA-2017-0384.html · Security Note
• https://advisories.mageia.org/MGASA-2017-0463.html · Security Note
• https://ubuntu.com/security/CVE-2017-11473 · Vendor Advisory
• https://ubuntu.com/security/CVE-2017-16531 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2017:2956-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2017-14991 · Vendor Advisory
• https://osv.dev/vulnerability/USN-3619-1 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2017:2869-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2018-10021 · Vendor Advisory