Linux Kernel up to 3.17 KEYS Subsystem keyring.c keyring_search_iterator null pointer dereference

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$0-$5k0.00

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 3.17 (Operating System). This issue affects the function keyring_search_iterator of the file keyring.c of the component KEYS Subsystem. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. The summary by CVE is:

The KEYS subsystem in the Linux kernel before 3.18 allows local users to gain privileges or cause a denial of service (NULL pointer dereference and system crash) via vectors involving a NULL value for a certain match field, related to the keyring_search_iterator function in keyring.c.

The bug was discovered 03/02/2017. The weakness was released 03/31/2017 as confirmed git commit (GIT Repository). The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2017-2647 since 12/01/2016. An attack has to be approached locally. A simple authentication is required for exploitation. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 18 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 97986 (Virtuozzo 6 : parallels-server-bm-release / vzkernel / etc (VZA-2017-019)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Virtuozzo Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 197333 (Ubuntu Security Notification for Linux Vulnerabilities (USN-3849-1)).

Upgrading to version 3.18 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (97986).

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

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

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
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: 97986
Nessus Name: Virtuozzo 6 : parallels-server-bm-release / vzkernel / etc (VZA-2017-019)
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: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 3.18
Patch: git.kernel.org

Timelineinfo

12/01/2016 🔍
03/02/2017 +91 days 🔍
03/20/2017 +18 days 🔍
03/21/2017 +1 days 🔍
03/27/2017 +6 days 🔍
03/31/2017 +4 days 🔍
03/31/2017 +0 days 🔍
03/31/2017 +0 days 🔍
11/24/2022 +2064 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: RHSA-2017:1842
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-2647 (🔍)
SecurityFocus: 97258 - Linux Kernel CVE-2017-2647 Null Pointer Deference Local Privilege Escalation Vulnerability
OSVDB: - CVE-2017-2647 - Linux - Privilege Escalation Issue

Entryinfo

Created: 03/31/2017 09:15
Updated: 11/24/2022 09:47
Changes: 03/31/2017 09:15 (79), 08/24/2020 09:33 (6), 11/24/2022 09:47 (4)
Complete: 🔍

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