Linux Kernel 3.8.2 chroot CLONE_NEWUSER access control

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

Summaryinfo

A vulnerability was found in Linux Kernel 3.8.2 and classified as problematic. Affected by this issue is the function CLONE_NEWUSER of the component chroot Handler. The manipulation results in access control. This vulnerability was named CVE-2013-1858. In addition, an exploit is available. It is best practice to apply a patch to resolve this issue.

Detailsinfo

A vulnerability was found in Linux Kernel 3.8.2 (Operating System). It has been classified as critical. Affected is the function CLONE_NEWUSER of the component chroot Handler. The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-264. This is going to have an impact on confidentiality, and integrity. CVE summarizes:

The clone system-call implementation in the Linux kernel before 3.8.3 does not properly handle a combination of the CLONE_NEWUSER and CLONE_FS flags, which allows local users to gain privileges by calling chroot and leveraging the sharing of the / directory between a parent process and a child process.

The weakness was presented 03/13/2013 by Sebastian Krahmer as CLONE_NEWUSER|CLONE_FS root exploit as not defined mailinglist post (oss-sec). The advisory is available at seclists.org. The vendor was not involved in the coordination of the public release. This vulnerability is traded as CVE-2013-1858 since 02/19/2013. Local access is required to approach this attack. A authentication is needed for exploitation. Technical details and a public exploit are known. This vulnerability is assigned to T1068 by the MITRE ATT&CK project.

A public exploit has been developed by Sebastian Krahmer in ANSI C and been published immediately after the advisory. The exploit is shared for download at stealth.openwall.net. It is declared as proof-of-concept. As 0-day the estimated underground price was around $25k-$100k.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org.

The vulnerability is also documented in the databases at X-Force (82815), SecurityFocus (BID 58478†), OSVDB (91275†), Secunia (SA52305†) and Vulnerability Center (SBV-38772†). Further details are available at seclists.org. See VDB-7997 and VDB-7994 for similar entries. 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: 7.1
VulDB Meta Temp Score: 6.4

VulDB Base Score: 7.1
VulDB Temp Score: 6.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Sebastian Krahmer
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Patch: git.kernel.org

Timelineinfo

02/19/2013 🔍
03/13/2013 +22 days 🔍
03/13/2013 +0 days 🔍
03/13/2013 +0 days 🔍
03/13/2013 +0 days 🔍
03/14/2013 +1 days 🔍
03/15/2013 +1 days 🔍
03/19/2013 +4 days 🔍
04/05/2013 +17 days 🔍
04/25/2017 +1481 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: CLONE_NEWUSER|CLONE_FS root exploit
Researcher: Sebastian Krahmer
Status: Not defined
Confirmation: 🔍

CVE: CVE-2013-1858 (🔍)
GCVE (CVE): GCVE-0-2013-1858
GCVE (VulDB): GCVE-100-7998
X-Force: 82815
SecurityFocus: 58478 - Linux Kernel 'CLONE_NEWUSER|CLONE_FS' Local Privilege Escalation Vulnerability
Secunia: 52305 - Linux Kernel User Namespace Sharing Privilege Escalation Vulnerability, Less Critical
OSVDB: 91275
Vulnerability Center: 38772 - Linux Kernel <3.8.3 Local Privilege Escalation Vulnerability Related to CLONE_NEWUSER and CLONE_FS, High

scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍
See also: 🔍

Entryinfo

Created: 03/15/2013 11:56
Updated: 04/25/2017 23:01
Changes: 03/15/2013 11:56 (78), 04/25/2017 23:01 (2)
Complete: 🔍
Cache ID: 216:E54:103

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