Linux Kernel up to 4.12.4 fsnotify Crafted Application race condition

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 4.12.4 and classified as problematic. Affected by this issue is some unknown functionality of the component fsnotify. Such manipulation as part of Crafted Application leads to race condition. This vulnerability is traded as CVE-2017-7533. An attack has to be approached locally. Furthermore, there is an exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 4.12.4 (Operating System) and classified as problematic. Affected by this issue is an unknown code of the component fsnotify. The manipulation as part of a Crafted Application 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. CVE summarizes:

Race condition in the fsnotify implementation in the Linux kernel through 4.12.4 allows local users to gain privileges or cause a denial of service (memory corruption) via a crafted application that leverages simultaneous execution of the inotify_handle_event and vfs_rename functions, as exploited in the wild in August 2017.

The bug was discovered 08/04/2017. The weakness was shared 08/05/2017 (Website). The advisory is shared for download at kernel.org. This vulnerability is handled as CVE-2017-7533 since 04/05/2017. The attack needs to be approached locally. A simple authentication is needed for exploitation. Technical details are unknown but a public exploit is available.

The exploit is available at exploit-db.com. It is declared as attacked. The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 102544 (Amazon Linux AMI : kernel (ALAS-2017-870)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 351447 (Amazon Linux Security Advisory for kernel: ALAC2012-2018-013).

Upgrading 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 Exploit-DB (44302), Zero-Day.cz (466), Tenable (102544), SecurityFocus (BID 100123†) and SecurityTracker (ID 1039075†). The entries VDB-75570, VDB-93980, VDB-94739 and VDB-98332 are 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: 6.1
VulDB Meta Temp Score: 6.0

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

NVD Base Score: 7.0
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Attacked
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 102544
Nessus Name: Amazon Linux AMI : kernel (ALAS-2017-870)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703926
OpenVAS Name: Debian Security Advisory DSA 3927-1 (linux - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍
Zero-Day.cz: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Patch: git.kernel.org

Timelineinfo

04/05/2017 🔍
08/03/2017 +120 days 🔍
08/04/2017 +1 days 🔍
08/04/2017 +0 days 🔍
08/05/2017 +1 days 🔍
08/05/2017 +0 days 🔍
08/06/2017 +1 days 🔍
08/17/2017 +11 days 🔍
08/18/2017 +1 days 🔍
07/05/2024 +2513 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: RHSA-2017:2473
Researcher: Fan Wu, Shixiong Zhao
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-7533 (🔍)
GCVE (CVE): GCVE-0-2017-7533
GCVE (VulDB): GCVE-100-104864

OVAL: 🔍

SecurityFocus: 100123 - Linux Kernel CVE-2017-7533 Local Race Condition Vulnerability
SecurityTracker: 1039075

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

Entryinfo

Created: 08/06/2017 14:20
Updated: 07/05/2024 18:45
Changes: 08/06/2017 14:20 (84), 02/07/2020 08:19 (9), 01/07/2021 12:17 (3), 12/15/2022 07:20 (4), 07/05/2024 18:45 (21)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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