Auth bypass in Linux Kernel
CVE-2019-3887
A flaw was found in the way KVM hypervisor handled x2APIC Machine Specific Rregister (MSR) access with nested(=1) virtualization enabled. In that, L1 guest could access L0's APIC register values via L2 guest, when 'virtualize x2APIC mode' is enabled. A guest could use this flaw to potentially crash the host kernel resulting in DoS issue. Kernel versions from 4.16 and newer are vulnerable to this issue.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.6 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (27.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Linux Kernel
- The Linux Foundation Kernel — versions from 4.16
- Canonical Ubuntu Linux — versions 18.04, 18.10, 19.04
- Fedoraproject Fedora — versions 29
- Red Hat Enterprise Linux — versions 8.0
- Red Hat Enterprise Linux Eus — versions 8.1, 8.2, 8.4
- Red Hat Enterprise Linux For Real Time — versions 8
- Red Hat Enterprise Linux For Real Time Nfv — versions 8
- Red Hat Enterprise Linux For Real Time Nfv Tus — versions 8.2, 8.4
- Red Hat Enterprise Linux For Real Time Tus — versions 8.2, 8.4
Weakness classification (CWE)
References
- www.securityfocus.com/bid/107850 (VDB Entry, Third Party Advisory, vdb-entry)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- usn.ubuntu.com/3980-1/ (vendor-advisory, Third Party Advisory)
- usn.ubuntu.com/3979-1/ (vendor-advisory, Third Party Advisory)
- usn.ubuntu.com/3980-2/ (vendor-advisory, Third Party Advisory)
- access.redhat.com/errata/RHSA-2019:2703 (vendor-advisory, Third Party Advisory)
- access.redhat.com/errata/RHSA-2019:2741 (vendor-advisory, Third Party Advisory)
- bugzilla.redhat.com/show_bug.cgi (Patch, Third Party Advisory, Issue Tracking)
Frequently asked questions
- What is CVE-2019-3887?
- CVE-2019-3887 is a medium-severity vulnerability in Linux Kernel, classified under Incorrect Authorization. CVSS score: 5.6/10. Published 2019-04-09.
- How severe is CVE-2019-3887?
- Medium severity. CVSS v3 base score is 5.6 out of 10.