Linux Kernel up to 4.6.3 on PowerPC process.c start_thread input validation

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in Linux Kernel up to 4.6.3 on PowerPC. This issue affects the function start_thread of the file arch/powerpc/kernel/process.c. Executing a manipulation can lead to input validation. This vulnerability appears as CVE-2016-5828. The attack requires local access. There is no available exploit. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in Linux Kernel up to 4.6.3 on PowerPC (Operating System). It has been declared as critical. This vulnerability affects the function start_thread of the file arch/powerpc/kernel/process.c. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

The start_thread function in arch/powerpc/kernel/process.c in the Linux kernel through 4.6.3 on powerpc platforms mishandles transactional state, which allows local users to cause a denial of service (invalid process state or TM Bad Thing exception, and system crash) or possibly have unspecified other impact by starting and suspending a transaction before an exec system call.

The weakness was presented 06/27/2016 by Michael Ellerman (oss-sec). The advisory is available at openwall.com. This vulnerability was named CVE-2016-5828. The exploitation appears to be easy. Local access is required to approach this attack. A single authentication is necessary for exploitation. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 91927 (Debian DSA-3616-1 : linux - security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 157314 (Oracle Enterprise Linux Security Update for kernel (ELSA-2016-2574)-Deprecated).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at patchwork.ozlabs.org. A possible mitigation has been published even before and not after the disclosure of the vulnerability. The vulnerability will be addressed with the following lines of code:

#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
        /*
        * Clear any transactional state, we're exec()ing. The cause is
        * not important as there will never be a recheckpoint so it's not
        * user visible.
        */
       if (MSR_TM_SUSPENDED(mfmsr()))
               tm_reclaim_current(0);
#endif

The vulnerability is also documented in the databases at Tenable (91927) and SecurityFocus (BID 91415†). See VDB-82951, VDB-82953, VDB-82963 and VDB-82965 for similar entries. Once again VulDB remains the best source for vulnerability data.

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.6

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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Exploitinginfo

Class: Input validation
CWE: CWE-20
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: 91927
Nessus Name: Debian DSA-3616-1 : linux - security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 863279
OpenVAS Name: RedHat Update for kernel RHSA-2016:2574-02
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: patchwork.ozlabs.org

Timelineinfo

06/17/2016 🔍
06/23/2016 +5 days 🔍
06/24/2016 +1 days 🔍
06/27/2016 +3 days 🔍
06/27/2016 +0 days 🔍
06/29/2016 +2 days 🔍
07/05/2016 +6 days 🔍
08/25/2022 +2242 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: USN-3070-1
Researcher: Michael Ellerman
Status: Confirmed

CVE: CVE-2016-5828 (🔍)
GCVE (CVE): GCVE-0-2016-5828
GCVE (VulDB): GCVE-100-88378

OVAL: 🔍

SecurityFocus: 91415 - Linux Kernel 'kernel/process.c' Local Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 06/29/2016 11:21
Updated: 08/25/2022 13:11
Changes: 06/29/2016 11:21 (71), 02/12/2019 11:01 (11), 08/25/2022 13:04 (5), 08/25/2022 13:11 (1)
Complete: 🔍
Cache ID: 216:6BC:103

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