CVE-2019-18421 — Race Condition in XEN
Severity
7.5HIGHNVD
NVD6.6
EPSS
1.9%
top 16.91%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedOct 31
Latest updateMay 24
Description
An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to gain host OS privileges by leveraging race conditions in pagetable promotion and demotion operations. There are issues with restartable PV type change operations. To avoid using shadow pagetables for PV guests, Xen exposes the actual hardware pagetables to the guest. In order to prevent the guest from modifying these page tables directly, Xen keeps track of how pages are used using a type system; pages must be "promo…
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HExploitability: 1.6 | Impact: 5.9
Affected Packages4 packages
Also affects: Debian Linux 10.0, 9.0, Fedora 29, 30, 31
Patches
🔴Vulnerability Details
4📋Vendor Advisories
4Red Hat▶
xen: a malicious PV guest administrator may be able to escalate their privilege to that of the host↗2019-10-31
Debian▶
CVE-2019-19580: xen - An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to ...↗2019
Debian▶
CVE-2019-18421: xen - An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to ...↗2019