Xen Security 4.2 Hypercall FLASK_AVC_CACHESTAT numeric error

CVSS Meta Temp Score
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4.5$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Xen Security 4.2. This issue affects the function FLASK_AVC_CACHESTAT of the component Hypercall Handler. Such manipulation leads to numeric error. This vulnerability is documented as CVE-2014-1895. There is not any exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Xen Security 4.2 (Virtualization Software) and classified as problematic. Affected by this issue is the function FLASK_AVC_CACHESTAT of the component Hypercall Handler. The manipulation with an unknown input leads to a numeric error vulnerability. Using CWE to declare the problem leads to CWE-189. Impacted is confidentiality, and availability. CVE summarizes:

Off-by-one error in the flask_security_avc_cachestats function in xsm/flask/flask_op.c in Xen 4.2.x and 4.3.x, when the maximum number of physical CPUs are in use, allows local users to cause a denial of service (host crash) or obtain sensitive information from hypervisor memory by leveraging a FLASK_AVC_CACHESTAT hypercall, which triggers a buffer over-read.

The weakness was released 02/06/2014 by Matthew Daley as Xen Security Advisory CVE-2014-1895 / XSA-85 as confirmed advisory (Website). The advisory is shared for download at xenbits.xenproject.org. The public release was coordinated with the vendor. This vulnerability is handled as CVE-2014-1895 since 02/07/2014. The exploitation is known to be easy. The attack needs to be approached locally. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 72539 (Fedora 20 : xen-4.3.1-9.fc20 (2014-2170)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 166935 (OpenSuSE Security Update for xen (openSUSE-SU-2014:0483-1)).

Applying the patch xsa85.patch is able to eliminate this problem. The bugfix is ready for download at xenbits.xenproject.org.

The vulnerability is also documented in the databases at X-Force (91005), Tenable (72539), SecurityFocus (BID 65414†), Secunia (SA56746†) and Vulnerability Center (SBV-43665†). cve.mitre.org is providing further details. Entries connected to this vulnerability are available at VDB-11164, VDB-12064, VDB-12235 and VDB-12339. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 4.5

VulDB Base Score: 5.1
VulDB Temp Score: 4.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Numeric error
CWE: CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 72539
Nessus Name: Fedora 20 : xen-4.3.1-9.fc20 (2014-2170)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

OpenVAS ID: 867511
OpenVAS Name: Fedora Update for xen FEDORA-2014-2170
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: xsa85.patch

Timelineinfo

02/06/2014 🔍
02/06/2014 +0 days 🔍
02/06/2014 +0 days 🔍
02/06/2014 +0 days 🔍
02/07/2014 +1 days 🔍
02/12/2014 +5 days 🔍
03/19/2014 +35 days 🔍
04/01/2014 +13 days 🔍
06/09/2021 +2626 days 🔍

Sourcesinfo

Advisory: Xen Security Advisory CVE-2014-1895 / XSA-85
Researcher: Matthew Daley
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2014-1895 (🔍)
GCVE (CVE): GCVE-0-2014-1895
GCVE (VulDB): GCVE-100-12236

OVAL: 🔍

X-Force: 91005 - Xen FLASK_AVC_CACHESTAT denial of service, Medium Risk
SecurityFocus: 65414
Secunia: 56746 - Xen FLASK_AVC_CACHESTAT Hypercall Vulnerability, Not Critical
Vulnerability Center: 43665 - Xen 4.2, 4.3 Local DoS and Information Disclosure Vulnerability due to Off-by-one Error in FLASK_AVC_CACHESTAT Hypercall, Low

Misc.: 🔍
See also: 🔍

Entryinfo

Created: 02/12/2014 14:04
Updated: 06/09/2021 09:04
Changes: 02/12/2014 14:04 (86), 05/23/2017 08:50 (1), 06/09/2021 09:04 (3)
Complete: 🔍
Committer:
Cache ID: 216:12B:103

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