Linux Kernel up to 5.8.1 fs/io_uring.c io_async_task_func use after free

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 5.8.1. Affected is the function io_async_task_func of the file fs/io_uring.c. Performing a manipulation results in use after free. This vulnerability is cataloged as CVE-2020-36387. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 5.8.1 (Operating System). This affects the function io_async_task_func of the file fs/io_uring.c. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was shared 06/08/2021. It is possible to read the advisory at sites.google.com. This vulnerability is uniquely identified as CVE-2020-36387. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 249996 (Linux Distros Unpatched Vulnerability : CVE-2020-36387), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.8.2 eliminates this vulnerability. The upgrade is hosted for download at cdn.kernel.org. Applying a patch 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 (249996). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Vendor

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 249996
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2020-36387

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.8.2
Patch: git.kernel.org

Timelineinfo

06/07/2021 🔍
06/08/2021 +1 days 🔍
06/08/2021 +0 days 🔍
08/17/2025 +1531 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: sites.google.com
Status: Confirmed

CVE: CVE-2020-36387 (🔍)
GCVE (CVE): GCVE-0-2020-36387
GCVE (VulDB): GCVE-100-176439

Entryinfo

Created: 06/08/2021 08:05
Updated: 08/17/2025 22:50
Changes: 06/08/2021 08:05 (43), 06/10/2021 14:17 (5), 08/17/2025 22:50 (16)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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