Linux Kernel up to 5.12.6 uio_hv_generic vmbus_alloc_ring memory leak

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.12.6 and classified as critical. The affected element is the function vmbus_alloc_ring of the component uio_hv_generic. Executing a manipulation can lead to memory leak. This vulnerability appears as CVE-2021-47070. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 5.12.6 (Operating System). This vulnerability affects the function vmbus_alloc_ring of the component uio_hv_generic. The manipulation with an unknown input leads to a memory leak vulnerability. The CWE definition for the vulnerability is CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: uio_hv_generic: Fix another memory leak in error handling paths Memory allocated by 'vmbus_alloc_ring()' at the beginning of the probe function is never freed in the error handling path. Add the missing 'vmbus_free_ring()' call. Note that it is already freed in the .remove function.

The weakness was presented 03/02/2024. The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2021-47070 since 02/29/2024. There are known technical details, 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 5.12.7 or 5.13 eliminates this vulnerability. Applying the patch 5f59240cf25b/0b0226be3a52 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). 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: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Memory leak
CWE: CWE-401 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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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 5.12.7/5.13
Patch: 5f59240cf25b/0b0226be3a52

Timelineinfo

02/29/2024 🔍
03/02/2024 +2 days 🔍
03/02/2024 +0 days 🔍
11/23/2025 +631 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-47070 (🔍)
GCVE (CVE): GCVE-0-2021-47070
GCVE (VulDB): GCVE-100-255448

Entryinfo

Created: 03/02/2024 05:15
Updated: 11/23/2025 18:24
Changes: 03/02/2024 05:15 (44), 11/04/2024 21:06 (26), 11/23/2025 18:24 (2)
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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