Linux Kernel up to 4.10.2 System Call kernel/ucount.c use after free

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in Linux Kernel up to 4.10.2. The impacted element is an unknown function of the file kernel/ucount.c of the component System Call Handler. The manipulation results in use after free. This vulnerability is identified as CVE-2017-6874. The attack is only possible with local access. There is not any exploit available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 4.10.2 (Operating System). Affected is an unknown functionality of the file kernel/ucount.c of the component System Call Handler. 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 availability. CVE summarizes:

Race condition in kernel/ucount.c in the Linux kernel through 4.10.2 allows local users to cause a denial of service (use-after-free and system crash) or possibly have unspecified other impact via crafted system calls that leverage certain decrement behavior that causes incorrect interaction between put_ucounts and get_ucounts.

The bug was discovered 03/14/2017. The weakness was released 03/14/2017 as confirmed git commit (GIT Repository). The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2017-6874 since 03/14/2017. The attack needs to be approached locally. The successful exploitation needs a authentication. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 99010 (Fedora 25 : kernel (2017-90aaa5bd24)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 351446 (Amazon Linux Security Advisory for kernel: ALAC2012-2018-012).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. A possible mitigation has been published 2 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (99010) and SecurityFocus (BID 96856†). Entries connected to this vulnerability are available at VDB-96555, VDB-96560, VDB-96561 and VDB-96562. VulDB is the best source for vulnerability data and more expert information about this specific topic.

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: 5.1

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.0
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
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: 99010
Nessus Name: Fedora 25 : kernel (2017-90aaa5bd24)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for kernel FEDORA-2017-90aaa5bd24
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: git.kernel.org

Timelineinfo

03/14/2017 🔍
03/14/2017 +0 days 🔍
03/14/2017 +0 days 🔍
03/14/2017 +0 days 🔍
03/14/2017 +0 days 🔍
03/14/2017 +0 days 🔍
03/27/2017 +13 days 🔍
03/28/2017 +1 days 🔍
09/06/2020 +1258 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-6874 (🔍)
GCVE (CVE): GCVE-0-2017-6874
GCVE (VulDB): GCVE-100-97896
SecurityFocus: 96856 - Linux kernel CVE-2017-6874 Use After Free Local Denial of Service Vulnerability
OSVDB: - CVE-2017-6874 - Linux - Use-After-Free Issue

See also: 🔍

Entryinfo

Created: 03/14/2017 15:05
Updated: 09/06/2020 12:38
Changes: 03/14/2017 15:05 (79), 09/06/2020 12:38 (6)
Complete: 🔍
Cache ID: 216::103

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