Linux Kernel up to 4.11 fs/f2fs/node.c add_free_nid race condition

CVSS Meta Temp Score
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CTI Interest Score
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5.6$0-$5k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 4.11 and classified as critical. This vulnerability affects the function add_free_nid of the file fs/f2fs/node.c. Performing a manipulation results in race condition. This vulnerability is identified as CVE-2017-18249. The attack is only possible with local access. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 4.11 (Operating System). This affects the function add_free_nid of the file fs/f2fs/node.c. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

The add_free_nid function in fs/f2fs/node.c in the Linux kernel before 4.12 does not properly track an allocated nid, which allows local users to cause a denial of service (race condition) or possibly have unspecified other impact via concurrent threads.

The bug was discovered 03/24/2018. The weakness was released 03/26/2018 (Website). The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2017-18249 since 03/26/2018. An attack has to be approached locally. A authentication is necessary for exploitation. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 2 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 110658 (openSUSE Security Update : the Linux Kernel (openSUSE-2018-656) (Spectre)), 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 176702 (Debian Security Update for linux-4.9 (DLA 1715-1)).

Upgrading to version 4.12 eliminates this vulnerability. A possible mitigation has been published 4 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (110658) and SecurityFocus (BID 107127†). Entries connected to this vulnerability are available at VDB-119428, VDB-120148, VDB-122246 and VDB-130385. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.6

VulDB Base Score: 4.4
VulDB Temp Score: 4.2
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: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 110658
Nessus Name: openSUSE Security Update : the Linux Kernel (openSUSE-2018-656) (Spectre)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: Kernel 4.12
Patch: git.kernel.org

Timelineinfo

03/24/2018 🔍
03/26/2018 +2 days 🔍
03/26/2018 +0 days 🔍
03/26/2018 +0 days 🔍
03/27/2018 +1 days 🔍
06/21/2018 +86 days 🔍
06/22/2018 +1 days 🔍
02/15/2019 +238 days 🔍
02/24/2023 +1470 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: 30a61ddf8117c26ac5b295e1233eaa9629a94ca3
Status: Confirmed

CVE: CVE-2017-18249 (🔍)
GCVE (CVE): GCVE-0-2017-18249
GCVE (VulDB): GCVE-100-115041
SecurityFocus: 107127 - Linux Kernel CVE-2019-6974 Security Bypass Vulnerability
SecurityTracker: 1041432

See also: 🔍

Entryinfo

Created: 03/27/2018 09:17
Updated: 02/24/2023 09:19
Changes: 03/27/2018 09:17 (79), 01/16/2020 19:18 (4), 02/24/2023 09:18 (6), 02/24/2023 09:19 (1)
Complete: 🔍
Cache ID: 216:121:103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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