CVE-2019-18421
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
02 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
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 1.67% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 76.4% of scored records. A rank, not a probability.
- NVD base score
- 7.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2019-10-31 13:34Z7 YR AGO
- Last updated
- 2024-08-05 01:54Z2 YR AGO
- Reserved
- 2019-10-24
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- Not rated by the issuing CNA
- CNA CVSS vector
- Not published by the issuing CNA
- Weaknesses
- Data version
- 5.1
- Document digest
- a05b75cda557db559d8094b2479ef3043f3f5daaf3c1d76704f9654934da1df0
05 Affected products
06 References
- xenbits.xen.orghttp://xenbits.xen.org/xsa/advisory-299.html
- www.openwall.com[oss-security] 20191031 Xen Security Advisory 299 v4 (CVE-2019-18421) - Issues with restartable PV type change operationshttp://www.openwall.com/lists/oss-security/2019/10/31/3
- lists.opensuse.orgopenSUSE-SU-2019:2506http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00037.html
- lists.fedoraproject.orgFEDORA-2019-865bb16900https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2BQKX7M2RHCWDBKNPX4KEBI3MJIH6AYZ/
- lists.fedoraproject.orgFEDORA-2019-376ec5c107https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I5WWPW4BSZDDW7VHU427XTVXV7ROOFFW/
- lists.fedoraproject.orgFEDORA-2019-cbb732f760https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IZYATWNUGHRBG6I3TC24YHP5Y3J7I6KH/
- www.debian.orgDSA-4602https://www.debian.org/security/2020/dsa-4602
- seclists.org20200114 [SECURITY] [DSA 4602-1] xen security updatehttps://seclists.org/bugtraq/2020/Jan/21
- security.gentoo.orgGLSA-202003-56https://security.gentoo.org/glsa/202003-56
07 Fixed in
Debian 12
- xen Fixed in 4.11.3+24-g14b62ab3e5-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- xen Fixed in 4.11.3+24-g14b62ab3e5-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- xen Fixed in 4.11.3+24-g14b62ab3e5-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 16.04 LTS
- xen No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 18.04 LTS
- xen No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.