CVE-2018-12891
Xen PV Guest CPU Preemption Denial of Service Explore
Description
An issue was discovered in Xen through 4.10.x. Certain PV MMU operations may take a long time to process. For that reason Xen explicitly checks for the need to preempt the current vCPU at certain points. A few rarely taken code paths did bypass such checks. By suitably enforcing the conditions through its own page table contents, a malicious guest may cause such bypasses to be used for an unbounded number of iterations. A malicious or buggy PV guest may cause a Denial of Service (DoS) affecting the entire host. Specifically, it may prevent use of a physical CPU for an indeterminate period of time. All Xen versions from 3.4 onwards are vulnerable. Xen versions 3.3 and earlier are vulnerable to an even wider class of attacks, due to them lacking preemption checks altogether in the affected code paths. Only x86 systems are affected. ARM systems are not affected. Only multi-vCPU x86 PV guests can leverage the vulnerability. x86 HVM or PVH guests as well as x86 single-vCPU PV ones cannot leverage the vulnerability.
INFO
Published Date :
July 2, 2018, 5:29 p.m.
Last Modified :
Oct. 3, 2019, 12:03 a.m.
Source :
[email protected]
Remotely Exploitable :
No
Impact Score :
4.0
Exploitability Score :
2.0
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2018-12891.
| URL | Resource |
|---|---|
| http://www.openwall.com/lists/oss-security/2018/06/27/10 | Mailing List Patch Third Party Advisory |
| http://www.securityfocus.com/bid/104570 | Third Party Advisory VDB Entry |
| http://www.securitytracker.com/id/1041201 | Third Party Advisory VDB Entry |
| http://xenbits.xen.org/xsa/advisory-264.html | Patch Vendor Advisory |
| https://lists.debian.org/debian-lts-announce/2018/11/msg00013.html | Issue Tracking Third Party Advisory |
| https://security.gentoo.org/glsa/201810-06 | Third Party Advisory |
| https://support.citrix.com/article/CTX235748 | Third Party Advisory |
| https://www.debian.org/security/2018/dsa-4236 | Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2018-12891 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2018-12891 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
CWE Remap by [email protected]
Oct. 03, 2019
Action Type Old Value New Value Changed CWE CWE-399 CWE-400 NVD-CWE-noinfo -
Modified Analysis by [email protected]
Mar. 29, 2019
Action Type Old Value New Value Changed Reference Type https://lists.debian.org/debian-lts-announce/2018/11/msg00013.html No Types Assigned https://lists.debian.org/debian-lts-announce/2018/11/msg00013.html Issue Tracking, Third Party Advisory Changed Reference Type https://security.gentoo.org/glsa/201810-06 No Types Assigned https://security.gentoo.org/glsa/201810-06 Third Party Advisory Changed CPE Configuration OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* OR *cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* -
CVE Modified by [email protected]
Nov. 13, 2018
Action Type Old Value New Value Added Reference https://lists.debian.org/debian-lts-announce/2018/11/msg00013.html [No Types Assigned] -
CVE Modified by [email protected]
Oct. 31, 2018
Action Type Old Value New Value Added Reference https://security.gentoo.org/glsa/201810-06 [No Types Assigned] -
Initial Analysis by [email protected]
Sep. 04, 2018
Action Type Old Value New Value Added CVSS V2 (AV:L/AC:L/Au:N/C:N/I:N/A:C) Added CVSS V3 AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H Changed Reference Type http://www.securityfocus.com/bid/104570 No Types Assigned http://www.securityfocus.com/bid/104570 Third Party Advisory, VDB Entry Changed Reference Type https://support.citrix.com/article/CTX235748 No Types Assigned https://support.citrix.com/article/CTX235748 Third Party Advisory Changed Reference Type http://xenbits.xen.org/xsa/advisory-264.html No Types Assigned http://xenbits.xen.org/xsa/advisory-264.html Patch, Vendor Advisory Changed Reference Type http://www.securitytracker.com/id/1041201 No Types Assigned http://www.securitytracker.com/id/1041201 Third Party Advisory, VDB Entry Changed Reference Type https://www.debian.org/security/2018/dsa-4236 No Types Assigned https://www.debian.org/security/2018/dsa-4236 Third Party Advisory Changed Reference Type http://www.openwall.com/lists/oss-security/2018/06/27/10 No Types Assigned http://www.openwall.com/lists/oss-security/2018/06/27/10 Mailing List, Patch, Third Party Advisory Added CWE CWE-399 Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Added CPE Configuration OR *cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:* versions up to (including) 4.10.1 -
CVE Modified by [email protected]
Jul. 04, 2018
Action Type Old Value New Value Added Reference https://www.debian.org/security/2018/dsa-4236 [No Types Assigned] Added Reference https://support.citrix.com/article/CTX235748 [No Types Assigned] Added Reference http://www.securitytracker.com/id/1041201 [No Types Assigned]
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2018-12891 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2018-12891
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.06 }} 0.02%
score
0.24734
percentile