Linux Kernel eBPF bpf.c nsim_bpf_map_alloc information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel and classified as problematic. The impacted element is the function nsim_bpf_map_alloc of the file drivers/net/netdevsim/bpf.c of the component eBPF. Executing a manipulation can lead to information disclosure. The identification of this vulnerability is CVE-2021-4135. The attack may be launched remotely. There is no exploit available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as problematic was found in Linux Kernel (Operating System) (the affected version is unknown). This vulnerability affects the function nsim_bpf_map_alloc of the file drivers/net/netdevsim/bpf.c of the component eBPF. The manipulation with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality. CVE summarizes:

A memory leak vulnerability was found in the Linux kernel's eBPF for the Simulated networking device driver in the way user uses BPF for the device such that function nsim_map_alloc_elem being called. A local user could use this flaw to get unauthorized access to some data.

The weakness was shared 07/15/2022. The advisory is available at git.kernel.org. This vulnerability was named CVE-2021-4135 since 12/18/2021. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1592 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 236676 (Alibaba Cloud Linux 3 : 0029: cloud-kernel bugfix, enhancement and (ALINUX3-SA-2022:0029)), 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 git.kernel.org.

The vulnerability is also documented in the vulnerability database at Tenable (236676). 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: 4.9
VulDB Meta Temp Score: 4.8

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236676
Nessus Name: Alibaba Cloud Linux 3 : 0029: cloud-kernel bugfix, enhancement and (ALINUX3-SA-2022:0029)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: git.kernel.org

Timelineinfo

12/18/2021 🔍
07/15/2022 +208 days 🔍
07/15/2022 +0 days 🔍
05/18/2025 +1038 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-4135 (🔍)
GCVE (CVE): GCVE-0-2021-4135
GCVE (VulDB): GCVE-100-203914

Entryinfo

Created: 07/15/2022 07:19
Updated: 05/18/2025 16:20
Changes: 07/15/2022 07:19 (42), 07/31/2022 13:29 (11), 05/18/2025 16:20 (16)
Complete: 🔍
Cache ID: 216::103

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

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