XenSource Xen 4.4.x event_fifo.c cleanup_event_array use after free

CVSS Meta Temp Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in XenSource Xen 4.4.x. Affected by this issue is the function cleanup_event_array of the file event_fifo.c. Performing a manipulation results in use after free. This vulnerability is cataloged as CVE-2016-7154. The attack must be initiated from a local position. There is no exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability, which was classified as critical, was found in XenSource Xen 4.4.x (Virtualization Software). This affects the function cleanup_event_array of the file event_fifo.c. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Use-after-free vulnerability in the FIFO event channel code in Xen 4.4.x allows local guest OS administrators to cause a denial of service (host crash) and possibly execute arbitrary code or obtain sensitive information via an invalid guest frame number.

The weakness was shared 09/08/2016 by Mikhail Gorobets with Intel as XSA-188 as confirmed security advisory (Website). The advisory is shared at xenbits.xen.org. The vendor cooperated in the coordination of the public release. This vulnerability is uniquely identified as CVE-2016-7154 since 09/06/2016. The exploitability is told to be easy. It is possible to initiate the attack remotely. A authentication is needed for exploitation. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 94269 (SUSE SLES12 Security Update : xen (SUSE-SU-2016:2533-1) (Bunker Buster)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 175832 (Debian Security Update for xen (DSA 3663-1)).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at xenbits.xen.org. A possible mitigation has been published immediately after the disclosure of the vulnerability. The vulnerability will be addressed with the following lines of code:

d->evtchn_fifo = NULL;

The vulnerability is also documented in the databases at Tenable (94269), SecurityFocus (BID 92863†) and SecurityTracker (ID 1036754†). The entries VDB-91386, VDB-91387 and VDB-91388 are related to this item. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.6

VulDB Base Score: 6.7
VulDB Temp Score: 6.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.7
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 94269
Nessus Name: SUSE SLES12 Security Update : xen (SUSE-SU-2016:2533-1) (Bunker Buster)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 66197
OpenVAS Name: SuSE Update for xen openSUSE-SU-2016:2497-1 (xen)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: xenbits.xen.org

Timelineinfo

09/06/2016 🔍
09/08/2016 +2 days 🔍
09/08/2016 +0 days 🔍
09/08/2016 +0 days 🔍
09/09/2016 +1 days 🔍
09/09/2016 +0 days 🔍
09/21/2016 +12 days 🔍
10/26/2016 +35 days 🔍
04/12/2019 +898 days 🔍

Sourcesinfo

Vendor: citrix.com

Advisory: XSA-188
Researcher: Mikhail Gorobets
Organization: Intel
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2016-7154 (🔍)
GCVE (CVE): GCVE-0-2016-7154
GCVE (VulDB): GCVE-100-91389

OVAL: 🔍

SecurityFocus: 92863 - Xen CVE-2016-7154 Local Denial of Service Vulnerability
SecurityTracker: 1036754

See also: 🔍

Entryinfo

Created: 09/09/2016 10:40
Updated: 04/12/2019 10:39
Changes: 09/09/2016 10:40 (77), 04/12/2019 10:39 (13)
Complete: 🔍
Cache ID: 216:5DE:103

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