Executive Summary

Informations
Name CVE-2020-11739 First vendor Publication 2020-04-14
Vendor Cve Last vendor Modification 2020-07-13

Security-Database Scoring CVSS v3

Cvss vector : CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Overall CVSS Score 7.8
Base Score 7.8 Environmental Score 7.8
impact SubScore 6 Temporal Score 7.8
Exploitabality Sub Score 1.1
 
Attack Vector Local Attack Complexity High
Privileges Required Low User Interaction None
Scope Changed Confidentiality Impact High
Integrity Impact High Availability Impact High
Calculate full CVSS 3.0 Vectors scores

Security-Database Scoring CVSS v2

Cvss vector : (AV:L/AC:M/Au:N/C:C/I:C/A:C)
Cvss Base Score 6.9 Attack Range Local
Cvss Impact Score 10 Attack Complexity Medium
Cvss Expoit Score 3.4 Authentication None Required
Calculate full CVSS 2.0 Vectors scores

Detail

An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe anymore. The read-write locks are used in hypercalls (such as grant-table ones), so a malicious guest could exploit the race. For instance, there is a small window where Xen can leak memory if XENMAPSPACE_grant_table is used concurrently. A malicious guest may be able to leak memory, or cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded.

Original Source

Url : http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-11739

CWE : Common Weakness Enumeration

% Id Name
100 % CWE-119 Failure to Constrain Operations within the Bounds of a Memory Buffer

CPE : Common Platform Enumeration

TypeDescriptionCount
Application 18
Os 1
Os 198

Sources (Detail)

Source Url
CONFIRM http://xenbits.xen.org/xsa/advisory-314.html
DEBIAN https://www.debian.org/security/2020/dsa-4723
FEDORA https://lists.fedoraproject.org/archives/list/package-announce@lists.fedorapr...
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedorapr...
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedorapr...
GENTOO https://security.gentoo.org/glsa/202005-08
MISC https://xenbits.xen.org/xsa/advisory-314.html
MLIST http://www.openwall.com/lists/oss-security/2020/04/14/2
SUSE http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00006.html

Alert History

If you want to see full details history, please login or register.
0
1
Date Informations
2020-07-13 21:23:01
  • Multiple Updates
2020-05-23 02:35:26
  • First insertion