Linux Kernel BPF __cgroup_bpf_run_filter_getsockopt heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel. This affects the function __cgroup_bpf_run_filter_getsockopt of the component BPF. Performing a manipulation results in heap-based overflow. This vulnerability is reported as CVE-2021-20194. The attack requires a local approach. No exploit exists. It is advisable to use the suggested workaround.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel (Operating System) (version now known). This affects the function __cgroup_bpf_run_filter_getsockopt of the component BPF. The manipulation with an unknown input leads to a heap-based overflow vulnerability. CWE is classifying the issue as CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). This is going to have an impact on confidentiality, integrity, and availability.

The weakness was disclosed 02/24/2021. The advisory is shared at bugzilla.redhat.com. This vulnerability is uniquely identified as CVE-2021-20194. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 247100 (Linux Distros Unpatched Vulnerability : CVE-2021-20194), which helps to determine the existence of the flaw in a target environment.

The best possible mitigation is suggested to be Workaround.

The vulnerability is also documented in the vulnerability database at Tenable (247100). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 6.1

VulDB Base Score: 4.5
VulDB Temp Score: 4.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 247100
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2021-20194

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Workaround
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/17/2020 🔍
02/24/2021 +69 days 🔍
02/24/2021 +0 days 🔍
08/09/2025 +1627 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: bugzilla.redhat.com
Status: Confirmed

CVE: CVE-2021-20194 (🔍)
GCVE (CVE): GCVE-0-2021-20194
GCVE (VulDB): GCVE-100-170337

Entryinfo

Created: 02/24/2021 08:58
Updated: 08/09/2025 20:29
Changes: 02/24/2021 08:58 (39), 03/04/2021 21:18 (5), 03/04/2021 21:24 (18), 08/09/2025 20:29 (17)
Complete: 🔍
Cache ID: 216::103

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

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