CVE-2020-11739 Vulnerability Details

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CVE-2020-11739 Metadata Quick Info

CVE Published: 14/04/2020 | CVE Updated: 04/08/2024 | CVE Year: 2020
Source: mitre | Vendor: n/a | Product: n/a
Status : PUBLISHED

CVE-2020-11739 Description

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.

Metrics

CVSS Version: 3.1 | Base Score: n/a
Vector: n/a

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l➤ Impact Metrics:
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    Integrity Impact (I)*
    Availability Impact (A)*

Weakness Enumeration (CWE)

CWE-ID:
CWE Name: n/a
Source: n/a

Common Attack Pattern Enumeration and Classification (CAPEC)

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Source: NVD (National Vulnerability Database).