Linux Foundation Xen 4.3.0 Live Migration 64-bit PV Guest access control

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

A vulnerability, which was classified as critical, was found in Linux Foundation Xen 4.3.0 (Virtualization Software). This affects an unknown code block of the component Live Migration Handler. The manipulation as part of a 64-bit PV Guest leads to a access control vulnerability. CWE is classifying the issue as CWE-264. This is going to have an impact on confidentiality, and integrity. The summary by CVE is:

Xen 4.3.x writes hypervisor mappings to certain shadow pagetables when live migration is performed on hosts with more than 5TB of RAM, which allows local 64-bit PV guests to read or write to invalid memory and cause a denial of service (crash).
The advisory summarizes:
Xen 4.3.x and xen-unstable are vulnerable. Xen 4.2.x and earlier releases are not vulnerable.

The weakness was presented 09/30/2013 by Andrew Cooper as XSA-64 as confirmed mailinglist post (oss-sec). The advisory is shared at seclists.org. The public release was coordinated in cooperation with Linux Foundation. This vulnerability is uniquely identified as CVE-2013-4356 since 06/12/2013. An attack has to be approached locally. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1068 for this issue. The advisory points out:

On some hardware, during live migration of 64-bit PV guests, some parts of the guest's shadow pagetables are mistakenly filled in with hypervisor mappings. This causes Xen to crash when those mappings are later cleared. Before the crash, a malicious guest could use hypercalls to cause Xen to read and write the parts of memory pointed to by the stray mappings.

The vulnerability scanner Nessus provides a plugin with the ID 70421 (Fedora 20 : xen-4.3.0-7.fc20 (2013-18300)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks.

Applying the patch xsa64.patch is able to eliminate this problem. The mailinglist post contains the following remark:

Running only HVM and 32-bit PV guests or preventing live migration of 64-bit PV guests will avoid this issue.

The vulnerability is also documented in the databases at X-Force (87566), Tenable (70421), SecurityFocus (BID 62709†), OSVDB (97956†) and Secunia (SA54962†). See VDB-10531 for similar entry.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
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CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 4.9

VulDB Base Score: 5.1
VulDB Temp Score: 4.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 70421
Nessus Name: Fedora 20 : xen-4.3.0-7.fc20 (2013-18300)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: xsa64.patch

Timelineinfo

06/12/2013 🔍
09/30/2013 +110 days 🔍
09/30/2013 +0 days 🔍
09/30/2013 +0 days 🔍
10/01/2013 +1 days 🔍
10/03/2013 +2 days 🔍
10/09/2013 +6 days 🔍
12/15/2013 +67 days 🔍
05/26/2021 +2719 days 🔍

Sourcesinfo

Vendor: linuxfoundation.org

Advisory: XSA-64
Researcher: Andrew Cooper
Status: Confirmed
Coordinated: 🔍

CVE: CVE-2013-4356 (🔍)
X-Force: 87566
SecurityFocus: 62709
Secunia: 54962 - Xen 64-bit PV Guest Live Migration Hypervisor Memory Access Weakness, Not Critical
OSVDB: 97956
Vulnerability Center: 42573 - Xen 4.3.* Local Memory Read and Write and Denial of Service (CVE-2013-4356), Medium

See also: 🔍

Entryinfo

Created: 10/03/2013 11:54 AM
Updated: 05/26/2021 07:16 AM
Changes: 10/03/2013 11:54 AM (52), 05/17/2017 09:04 AM (27), 05/26/2021 07:16 AM (3)
Complete: 🔍
Cache ID: 18:750:40

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