CVE-2021-47408

Description

A vulnerability was found in the Linux kernel’s netfilter and conntrack module, occurring during the resizing and cleanup of hash tables used for connection tracking. The kernel's nf_ct_iterate_cleanup() function fails to efficiently handle simultaneous hash resizes and cleanups, leading to prolonged delays lead to unresponsive system behavior.

Statement

This vulnerability is rated as a moderate severity because it impacts on system availability rather than data security, affects system performance and responsiveness, particularly during cleanup operations under high load conditions

Mitigation

Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score4.75.54.7
Attack VectorLocalLocalLocal
Attack ComplexityHighLowHigh
Privileges RequiredLowLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityNoneNoneNone
Integrity ImpactNoneNoneNone
Availability ImpactHighHighHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

cve.org: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

CWE-667

Availability

Technical Impact: DoS: Resource Consumption (CPU)

Inconsistent locking discipline can lead to deadlock.

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