Linux Kernel up to 4.3.3 security/keys/keyctl.c keyctl_read_key race condition

CVSS Meta Temp Score
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6.1$0-$5k0.00

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 4.3.3 (Operating System). This issue affects the function keyctl_read_key of the file security/keys/keyctl.c. The manipulation with an unknown input leads to a race condition vulnerability. Using CWE to declare the problem leads to CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The keyctl_read_key function in security/keys/keyctl.c in the Linux kernel before 4.3.4 does not properly use a semaphore, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a crafted application that leverages a race condition between keyctl_revoke and keyctl_read calls.

The weakness was published 02/08/2016 with Google (Website). It is possible to read the advisory at security-tracker.debian.org. The identification of this vulnerability is CVE-2015-7550 since 09/29/2015. The exploitation is known to be easy. Attacking locally is a requirement. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 87738 (Debian DLA-378-1 : linux-2.6 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 168771 (SUSE Enterprise Linux Security update for the Linux Kernel (SUSE-SU-2016:1203-1)).

Upgrading to version 4.3.4 eliminates this vulnerability. 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 (87738). Similar entries are available at 8569, 78541, 79223 and 79228.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

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

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.1

VulDB Base Score: 7.0
VulDB Temp Score: 6.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
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: 87738
Nessus Name: Debian DLA-378-1 : linux-2.6 security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703434
OpenVAS Name: Debian Security Advisory DSA 3434-1 (linux - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 4.3.4
Patch: git.kernel.org

Timelineinfo

09/29/2015 🔍
12/09/2015 +72 days 🔍
12/22/2015 +13 days 🔍
01/04/2016 +13 days 🔍
01/05/2016 +1 days 🔍
02/07/2016 +32 days 🔍
02/08/2016 +1 days 🔍
02/08/2016 +0 days 🔍
02/08/2016 +0 days 🔍
07/07/2022 +2340 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: USN-2888-1
Organization: Google
Status: Not defined
Confirmation: 🔍

CVE: CVE-2015-7550 (🔍)
OVAL: 🔍

Vulnerability Center: 56445 - Linux Kernel before 4.3.4 Local DoS and Other Unspecified Impact due to a Race Condition in keyctl_read_key Function, Medium
SecurityFocus: 79903 - Linux Kernel CVE-2015-7550 Null Pointer Deference Local Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 02/08/2016 09:04
Updated: 07/07/2022 07:32
Changes: 02/08/2016 09:04 (74), 08/22/2018 09:41 (14), 07/07/2022 07:32 (5)
Complete: 🔍

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