Linux Kernel Device Hot-Unplugging postclose use after free

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.4$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel. Affected by this vulnerability is the function postclose of the component Device Hot-Unplugging. The manipulation results in use after free. This vulnerability is reported as CVE-2020-27820. An attack on the physical device is feasible. No exploit exists. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel (Operating System) (affected version not known). Affected is the function postclose of the component Device Hot-Unplugging. 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 disclosed 11/03/2021. The advisory is available at bugzilla.redhat.com. This vulnerability is traded as CVE-2020-27820 since 10/27/2020. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 276356 (TencentOS Server 3: kernel (TSSA-2023:0340)), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at lore.kernel.org.

The vulnerability is also documented in the vulnerability database at Tenable (276356). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.4

VulDB Base Score: 6.4
VulDB Temp Score: 6.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 4.7
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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

NVD Base Score: 🔍

Exploitinginfo

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

Physical: Yes
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 276356
Nessus Name: TencentOS Server 3: kernel (TSSA-2023:0340)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: lore.kernel.org

Timelineinfo

10/27/2020 🔍
11/03/2021 +372 days 🔍
11/03/2021 +0 days 🔍
11/23/2025 +1481 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: bugzilla.redhat.com
Status: Confirmed

CVE: CVE-2020-27820 (🔍)
GCVE (CVE): GCVE-0-2020-27820
GCVE (VulDB): GCVE-100-185922

Entryinfo

Created: 11/03/2021 07:28
Updated: 11/23/2025 12:06
Changes: 11/03/2021 07:28 (41), 11/06/2021 09:39 (19), 11/06/2021 09:43 (1), 11/23/2025 12:06 (16)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Do you want to use VulDB in your project?

Use the official API to access entries easily!