Linux Kernel up to 5.7 Nested Netlink Policy lib/nlattr.c denial of service

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

Summaryinfo

A vulnerability labeled as problematic has been found in Linux Kernel up to 5.7. This affects an unknown function in the library lib/nlattr.c of the component Nested Netlink Policy Handler. Such manipulation leads to denial of service. This vulnerability is traded as CVE-2020-36691. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 5.7 (Operating System). Affected by this issue is an unknown part in the library lib/nlattr.c of the component Nested Netlink Policy Handler. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. CVE summarizes:

An issue was discovered in the Linux kernel before 5.8. lib/nlattr.c allows attackers to cause a denial of service (unbounded recursion) via a nested Netlink policy with a back reference.

The weakness was shared 03/24/2023 as 7690aa1cdf7c4565ad6b013b324c28b685505e24. The advisory is available at github.com. This vulnerability is handled as CVE-2020-36691 since 03/24/2023. Technical details are known, but there is no available exploit.

Upgrading to version 5.8 eliminates this vulnerability. The upgrade is hosted for download at cdn.kernel.org. Applying the patch 7690aa1cdf7c4565ad6b013b324c28b685505e24 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

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

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: 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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.8
Patch: 7690aa1cdf7c4565ad6b013b324c28b685505e24

Timelineinfo

03/24/2023 🔍
03/24/2023 +0 days 🔍
03/24/2023 +0 days 🔍
04/14/2023 +21 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: 7690aa1cdf7c4565ad6b013b324c28b685505e24
Status: Confirmed

CVE: CVE-2020-36691 (🔍)
GCVE (CVE): GCVE-0-2020-36691
GCVE (VulDB): GCVE-100-223814

Entryinfo

Created: 03/24/2023 20:04
Updated: 04/14/2023 09:47
Changes: 03/24/2023 20:04 (46), 04/14/2023 09:47 (10)
Complete: 🔍
Cache ID: 216::103

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