CVE-2022-49110

netfilter: conntrack: revisit gc autotuning

Published Feb 26, 2025 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

netfilter: conntrack: revisit gc autotuning

as of commit 4608fdfc07e1
("netfilter: conntrack: collect all entries in one cycle")
conntrack gc was changed to run every 2 minutes.

On systems where conntrack hash table is set to large value, most evictions
happen from gc worker rather than the packet path due to hash table
distribution.

This causes netlink event overflows when events are collected.

This change collects average expiry of scanned entries and
reschedules to the average remaining value, within 1 to 60 second interval.

To avoid event overflows, reschedule after each bucket and add a
limit for both run time and number of evictions per run.

If more entries have to be evicted, reschedule and restart 1 jiffy
into the future.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2022-55102 In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: revisit gc autotuning as of commit 4608fdfc07e1 ("netfilter: conntrack: collect all entries in one cycle") conntrack gc was changed to run every 2 minutes. On systems where conntrack hash table is set to large value, most evictions happen from gc worker rather than the packet path due to hash table distribution. This causes netlink event overflows when events are collected. This change collects average expiry of scanned entries and reschedules to the average remaining value, within 1 to 60 second interval. To avoid event overflows, reschedule after each bucket and add a limit for both run time and number of evictions per run. If more entries have to be evicted, reschedule and restart 1 jiffy into the future.
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Type Values Removed Values Added
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: revisit gc autotuning as of commit 4608fdfc07e1 ("netfilter: conntrack: collect all entries in one cycle") conntrack gc was changed to run every 2 minutes. On systems where conntrack hash table is set to large value, most evictions happen from gc worker rather than the packet path due to hash table distribution. This causes netlink event overflows when events are collected. This change collects average expiry of scanned entries and reschedules to the average remaining value, within 1 to 60 second interval. To avoid event overflows, reschedule after each bucket and add a limit for both run time and number of evictions per run. If more entries have to be evicted, reschedule and restart 1 jiffy into the future.
Title netfilter: conntrack: revisit gc autotuning
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Oct 15, 2026, 9:21 PM
Reserved
Feb 26, 2025, 1:49 AM
Status
Modified
Published
Feb 26, 2025, 7:00 AM
Modified
Oct 15, 2026, 10:17 PM
Severity
Moderate
Public date
Feb 26, 2025, 12:00 AM