Linux Kernel up to 4.9.5 tmpfs System fs/posix_acl.c simple_set_acl access control

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 4.9.5. It has been rated as problematic. The impacted element is the function simple_set_acl of the file fs/posix_acl.c of the component tmpfs System. This manipulation causes access control. This vulnerability is registered as CVE-2017-5551. The attack needs to be launched locally. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 4.9.5 (Operating System) and classified as problematic. Affected by this vulnerability is the function simple_set_acl of the file fs/posix_acl.c of the component tmpfs System. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The simple_set_acl function in fs/posix_acl.c in the Linux kernel before 4.9.6 preserves the setgid bit during a setxattr call involving a tmpfs filesystem, which allows local users to gain group privileges by leveraging the existence of a setgid program with restrictions on execute permissions. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-7097.

The bug was discovered 02/06/2017. The weakness was published 02/06/2017 (Website). The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2017-5551 since 01/20/2017. An attack has to be approached locally. The successful exploitation requires a single authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1068 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 97297 (SUSE SLES11 Security Update : kernel (SUSE-SU-2017:0494-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276417 (Fedora Security Update for kernel (FEDORA-2017-6cc158c193)).

Upgrading to version 4.9.6 eliminates this vulnerability. A possible mitigation has been published 2 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (97297) and SecurityFocus (BID 95717†). Similar entries are available at VDB-96553, VDB-96554, VDB-96564 and VDB-96567. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.8

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 4.4
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
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: 97297
Nessus Name: SUSE SLES11 Security Update : kernel (SUSE-SU-2017:0494-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703791
OpenVAS Name: Debian Security Advisory DSA 3791-1 (linux - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: Kernel 4.9.6
Patch: git.kernel.org

Timelineinfo

01/20/2017 🔍
01/23/2017 +3 days 🔍
02/06/2017 +14 days 🔍
02/06/2017 +0 days 🔍
02/06/2017 +0 days 🔍
02/06/2017 +0 days 🔍
02/17/2017 +11 days 🔍
02/21/2017 +4 days 🔍
11/11/2022 +2089 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: 497de07d89c1410d76a15bec2bb41f24a2a89f31
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-5551 (🔍)
GCVE (CVE): GCVE-0-2017-5551
GCVE (VulDB): GCVE-100-96565

OVAL: 🔍

SecurityFocus: 95717 - Linux Kernel CVE-2017-5551 Local Denial of Service Vulnerability
OSVDB: - CVE-2017-5551 - Linux - Privilege Escalation Issue
SecurityTracker: 1038053

See also: 🔍

Entryinfo

Created: 02/06/2017 19:26
Updated: 11/11/2022 18:10
Changes: 02/06/2017 19:26 (87), 11/11/2022 18:10 (5)
Complete: 🔍
Cache ID: 216:7B5:103

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