Linux Kernel VFS Filesystem pivot_root resource management

CVSS Meta Temp Score
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CTI Interest Score
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3.8$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel and classified as problematic. This issue affects the function pivot_root of the component VFS Filesystem. The manipulation results in resource management. This vulnerability is cataloged as CVE-2014-7970. There is no exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel (Operating System) (the affected version is unknown). Affected is the function pivot_root of the component VFS Filesystem. The manipulation with an unknown input leads to a resource management vulnerability. CWE is classifying the issue as CWE-399. This is going to have an impact on availability.

The weakness was shared 10/08/2014 by Andy Lutomirski as Linux VFS denial of service as confirmed mailinglist post (oss-sec). The advisory is shared for download at seclists.org. The mailinglist post contains:

I'm posting this a little bit early, since a patch is publicly available, the impact is low, and hitting the bad code path at all is quite tedious.
This vulnerability is traded as CVE-2014-7970 since 10/08/2014. The exploitability is told to be difficult. The attack needs to be approached locally. A authentication is needed for exploitation. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 78800 (Fedora 21 : kernel-3.17.1-300.fc21 (2014-12955)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 157882 (Oracle Enterprise Linux Security Update for Unbreakable Enterprise kernel (ELSA-2018-4301)). The advisory illustrates:

I'll send a proof of concept later on.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at news.gmane.org. The vulnerability will be addressed with the following lines of code:

if (!is_path_reachable(new_mnt, new.dentry, &root))
   goto out4;
The mailinglist post contains the following remark:
Although, for validation, it should be sufficient to just chroot somewhere as root, escape the chroot (while still chrooted), and then pivot_root(".", ".") on a mountpoint.

The vulnerability is also documented in the databases at X-Force (96921), Tenable (78800), SecurityFocus (BID 70319†), Secunia (SA61142†) and SecurityTracker (ID 1030991†). The entry VDB-67766 is related to this item. 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: 4.0
VulDB Meta Temp Score: 3.8

VulDB Base Score: 2.5
VulDB Temp Score: 2.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Resource management
CWE: CWE-399 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 78800
Nessus Name: Fedora 21 : kernel-3.17.1-300.fc21 (2014-12955)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 867487
OpenVAS Name: Fedora Update for kernel FEDORA-2014-17283
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: news.gmane.org

Timelineinfo

10/08/2014 🔍
10/08/2014 +0 days 🔍
10/08/2014 +0 days 🔍
10/08/2014 +0 days 🔍
10/09/2014 +1 days 🔍
10/10/2014 +1 days 🔍
10/13/2014 +3 days 🔍
10/14/2014 +1 days 🔍
11/03/2014 +20 days 🔍
02/21/2022 +2667 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: Linux VFS denial of service
Researcher: Andy Lutomirski
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2014-7970 (🔍)
GCVE (CVE): GCVE-0-2014-7970
GCVE (VulDB): GCVE-100-67764

OVAL: 🔍

X-Force: 96921 - Linux Kernel VFS denial of service, Medium Risk
SecurityFocus: 70319 - Linux Kernel VFS 'pivot_root()' Function Denial of Service Vulnerability
Secunia: 61142
SecurityTracker: 1030991 - Linux Kernel VFS Filesystem Flaw Lets Local Users Deny Service
Vulnerability Center: 46428 - Linux Kernel through 3.17 Local DoS via . (dot) Values - CVE-2014-7970, Medium

See also: 🔍

Entryinfo

Created: 10/10/2014 13:24
Updated: 02/21/2022 15:05
Changes: 10/10/2014 13:24 (90), 06/08/2017 10:25 (2), 02/21/2022 14:57 (3), 02/21/2022 15:01 (11), 02/21/2022 15:05 (1)
Complete: 🔍
Cache ID: 216:B0B:103

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