Xen 4.10 MSR Emulation memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Xen 4.10. This issue affects some unknown processing of the component MSR Emulation. Executing a manipulation can lead to memory corruption. This vulnerability is tracked as CVE-2018-5244. The attack is restricted to local execution. No exploit exists. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability classified as problematic was found in Xen 4.10 (Virtualization Software). This vulnerability affects an unknown function of the component MSR Emulation. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect availability. CVE summarizes:

In Xen 4.10, new infrastructure was introduced as part of an overhaul to how MSR emulation happens for guests. Unfortunately, one tracking structure isn't freed when a vcpu is destroyed. This allows guest OS administrators to cause a denial of service (host OS memory consumption) by rebooting many times.

The bug was discovered 01/04/2018. The weakness was disclosed 01/05/2018 by Andrew Cooper with Citrix (Website). The advisory is shared for download at securityfocus.com. This vulnerability was named CVE-2018-5244 since 01/05/2018. The exploitation appears to be easy. The attack needs to be approached locally. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 105775 (Xen vcpu Destruction Handling Memory Exhaustion Guest-to-Host DoS (XSA-253)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Misc. and running in the context l.

Applying a patch is able to eliminate this problem. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (105775) and SecurityFocus (BID 102433†). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.1

VulDB Base Score: 3.8
VulDB Temp Score: 3.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 105775
Nessus Name: Xen vcpu Destruction Handling Memory Exhaustion Guest-to-Host DoS (XSA-253)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/04/2018 🔍
01/04/2018 +0 days 🔍
01/05/2018 +1 days 🔍
01/05/2018 +0 days 🔍
01/05/2018 +0 days 🔍
01/05/2018 +0 days 🔍
01/06/2018 +1 days 🔍
01/12/2018 +6 days 🔍
01/28/2021 +1112 days 🔍

Sourcesinfo

Advisory: securityfocus.com⛔
Researcher: Andrew Cooper
Organization: Citrix
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-5244 (🔍)
GCVE (CVE): GCVE-0-2018-5244
GCVE (VulDB): GCVE-100-111412
SecurityFocus: 102433 - Xen CVE-2018-5244 Memory Corruption Vulnerability
SecurityTracker: 1040774

Entryinfo

Created: 01/06/2018 17:15
Updated: 01/28/2021 18:03
Changes: 01/06/2018 17:15 (64), 12/19/2019 21:02 (8), 01/28/2021 18:03 (3)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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