Linux Kernel up to 4.6.2 net/netlink/af_netlink.c netlink_dump double free

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

A vulnerability was found in Linux Kernel up to 4.6.2 (Operating System) and classified as critical. This issue affects the function netlink_dump of the file net/netlink/af_netlink.c. The manipulation with an unknown input leads to a double free vulnerability. Using CWE to declare the problem leads to CWE-415. The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Race condition in the netlink_dump function in net/netlink/af_netlink.c in the Linux kernel before 4.6.3 allows local users to cause a denial of service (double free) or possibly have unspecified other impact via a crafted application that makes sendmsg system calls, leading to a free operation associated with a new dump that started earlier than anticipated.

The bug was discovered 12/28/2016. The weakness was presented 12/28/2016 (Website). It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2016-9806 since 12/04/2016. Attacking locally is a requirement. The successful exploitation requires a simple authentication. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 96477 (Oracle Linux 6 / 7 : Unbreakable Enterprise kernel (ELSA-2017-3508)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Oracle Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196664 (Ubuntu Security Notification for Linux Vulnerabilities (USN-3168-1)).

Upgrading to version 4.6.3 eliminates this vulnerability. A possible mitigation has been published 3 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (96477). See 94702, 94701, 94700 and 94699 for similar entries.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Double free
CWE: CWE-415 / CWE-119
ATT&CK: Unknown

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 96477
Nessus Name: Oracle Linux 6 / 7 : Unbreakable Enterprise kernel (ELSA-2017-3508)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 871165
OpenVAS Name: RedHat Update for kernel RHSA-2017:1842-01
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: Kernel 4.6.3
Patch: git.kernel.org

Timelineinfo

12/04/2016 🔍
12/05/2016 +1 days 🔍
12/28/2016 +23 days 🔍
12/28/2016 +0 days 🔍
12/28/2016 +0 days 🔍
12/28/2016 +0 days 🔍
01/12/2017 +15 days 🔍
01/13/2017 +1 days 🔍
10/12/2022 +2098 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: RHSA-2017:1842
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-9806 (🔍)
SecurityTracker: 1037968
SecurityFocus: 94653 - Linux Kernel CVE-2016-9806 Local Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 12/28/2016 16:11
Updated: 10/12/2022 20:55
Changes: 12/28/2016 16:11 (78), 07/20/2019 09:32 (6), 10/12/2022 20:55 (6)
Complete: 🔍

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