Linux Foundation Xen 4.4.0 on ARM Hardware Timer CNTKCTL_EL1 access control

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

Summaryinfo

A vulnerability marked as problematic has been reported in Linux Foundation Xen 4.4.0 on ARM. The affected element is an unknown function of the component Hardware Timer. This manipulation of the argument CNTKCTL_EL1 causes access control. The identification of this vulnerability is CVE-2014-3125. There is no exploit available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in Linux Foundation Xen 4.4.0 on ARM (Virtualization Software). It has been declared as problematic. Affected by this vulnerability is an unknown code of the component Hardware Timer. The manipulation of the argument CNTKCTL_EL1 with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect availability. The summary by CVE is:

Xen 4.4.x, when running on an ARM system, does not properly context switch the CNTKCTL_EL1 register, which allows local guest users to modify the hardware timers and cause a denial of service (crash) via unspecified vectors.

The weakness was shared 04/30/2014 by Chen Baozi as XSA-91 as confirmed advisory (Website). The advisory is shared at xenbits.xenproject.org. This vulnerability is known as CVE-2014-3125 since 04/29/2014. The exploitation appears to be difficult. An attack has to be approached locally. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1068 for this issue. The advisory points out:

A malicious guest kernel can reconfigure CNTKCTL_EL1 to block userspace access to the timer hardware for all domains, including control domains. Depending on the other guest kernels in use this may cause an unexpected exception in those guests which may lead to a kernel crash and therefore a denial of service. 64-bit ARM Linux is known to be susceptible to crashing in this way.

Applying the patch xsa91-4.4.patch is able to eliminate this problem. The bugfix is ready for download at xenbits.xenproject.org. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (92947), SecurityFocus (BID 67157†), Secunia (SA58347†), SecurityTracker (ID 1030184†) and Vulnerability Center (SBV-44373†). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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Website

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

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

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: xsa91-4.4.patch

Timelineinfo

04/29/2014 🔍
04/30/2014 +1 days 🔍
04/30/2014 +0 days 🔍
04/30/2014 +0 days 🔍
04/30/2014 +0 days 🔍
04/30/2014 +0 days 🔍
05/01/2014 +1 days 🔍
05/01/2014 +0 days 🔍
05/02/2014 +1 days 🔍
05/04/2014 +2 days 🔍
05/12/2026 +4391 days 🔍

Sourcesinfo

Vendor: linuxfoundation.org

Advisory: XSA-91
Researcher: Chen Baozi
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2014-3125 (🔍)
GCVE (CVE): GCVE-0-2014-3125
GCVE (VulDB): GCVE-100-13129
X-Force: 92947 - Xen CNTKCTL_EL1 register denial of service, Medium Risk
SecurityFocus: 67157 - Xen ARM 'CNTKCTL_EL1' Register Local Denial of Service Vulnerability
Secunia: 58347 - Xen ARM CNTKCTL_EL1 Register Handling Denial of Service Vulnerability, Not Critical
SecurityTracker: 1030184 - Xen CNTKCTL_EL1 Context Switching Flaw Lets Local Users Deny Service
Vulnerability Center: 44373 - Xen 4.4 on ARM Platform Local Security Bypass via CNTKCTL_EL1 Register, Medium

Entryinfo

Created: 05/02/2014 00:18
Updated: 05/12/2026 17:40
Changes: 05/02/2014 00:18 (77), 05/27/2017 10:37 (5), 05/12/2026 17:40 (17)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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