VDB-254785 · CVE-2020-36775 · Nessus 276342

Linux Kernel up to 5.4.188/5.6.6 f2fs f2fs_trylock_op deadlock

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5.0	$0-$5k	0.00

Summaryinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 5.4.188/5.6.6. This vulnerability affects the function f2fs_trylock_op of the component f2fs. This manipulation causes deadlock. This vulnerability is registered as CVE-2020-36775. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 5.4.188/5.6.6 (Operating System) and classified as problematic. Affected by this vulnerability is the function f2fs_trylock_op of the component f2fs. The manipulation with an unknown input leads to a deadlock vulnerability. The CWE definition for the vulnerability is CWE-833. The product contains multiple threads or executable segments that are waiting for each other to release a necessary lock, resulting in deadlock. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid potential deadlock Using f2fs_trylock_op() in f2fs_write_compressed_pages() to avoid potential deadlock like we did in f2fs_write_single_data_page().

The weakness was published 02/26/2024. The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2020-36775. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 276342 (TencentOS Server 2: kernel (TSSA-2024:0557)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.189, 5.6.7 or 5.7 eliminates this vulnerability. Applying the patch 0478ccdc8ea0/8e8542437bb4/df77fbd8c5b2 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (276342). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Operating System

Vendor

Linux

Name

Kernel

Version

License

open-source

Website

Vendor: https://www.kernel.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.0

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Deadlock
CWE: CWE-833 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
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Nessus ID: 276342
Nessus Name: TencentOS Server 2: kernel (TSSA-2024:0557)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.4.189/5.6.7/5.7
Patch: 0478ccdc8ea0/8e8542437bb4/df77fbd8c5b2

Timelineinfo

02/26/2024 🔍
02/26/2024 +0 days 🔍
02/26/2024 +0 days 🔍
11/23/2025 +636 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2020-36775 (🔍)
GCVE (CVE): GCVE-0-2020-36775
GCVE (VulDB): GCVE-100-254785

Entryinfo

Created: 02/26/2024 19:24
Updated: 11/23/2025 16:59
Changes: 02/26/2024 19:24 (43), 03/14/2024 10:11 (1), 07/11/2025 16:53 (27), 11/23/2025 16:59 (2)
Complete: 🔍
Cache ID: 216::103

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