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Full vulnerability report · 2024
CVE-2022-48974High confidence

netfilter: conntrack: fix using __this_cpu_add in preemptible

Linux · Linux

5.5MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

1 package state
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2022-53853

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: fix using __this_cpu_add in preemptible Currently in nf_conntrack_hash_check_insert(), when it fails in nf_ct_ext_valid_pre/post(), NF_CT_STAT_INC() will be called in the preemptible context, a call trace can be triggered: BUG: using __this_cpu_add() in preemptible [00000000] code: conntrack/1636 caller is nf_conntrack_hash_check_insert+0x45/0x430 [nf_conntrack] Call Trace: <TASK> dump_stack_lvl+0x33/0x46 check_preemption_disabled+0xc3/0xf0 nf_conntrack_hash_check_insert+0x45/0x430 [nf_conntrack] ctnetlink_create_conntrack+0x3cd/0x4e0 [nf_conntrack_netlink] ctnetlink_new_conntrack+0x1c0/0x450 [nf_conntrack_netlink] nfnetlink_rcv_msg+0x277/0x2f0 [nfnetlink] netlink_rcv_skb+0x50/0x100 nfnetlink_rcv+0x65/0x144 [nfnetlink] netlink_unicast+0x1ae/0x290 netlink_sendmsg+0x257/0x4f0 sock_sendmsg+0x5f/0x70 This patch is to fix it by changing to use NF_CT_STAT_INC_ATOMIC() for nf_ct_ext_valid_pre/post() check in nf_conntrack_hash_check_insert(), as well as nf_ct_ext_valid_post() in __nf_conntrack_confirm(). Note that nf_ct_ext_valid_pre() check in __nf_conntrack_confirm() is safe to use NF_CT_STAT_INC(), as it's under local_bh_disable().

What

In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: fix using __this_cpu_add in preemptible Currently in nf_conntrack_hash_check_insert(), when it fails in nf_ct_ext_valid_pre/post(), NF_CT_STAT_INC() will be called in the preemptible context, a call trace can be triggered: BUG: using __this_cpu_add() in preemptible [00000000] code: conntrack/1636 caller is nf_conntrack_hash_check_insert+0x45/0x430 [nf_conntrack] Call Trace: <TASK> dump_stack_lvl+0x33/0x46 check_preemption_disabled+0xc3/0xf0 nf_conntrack_hash_check_insert+0x45/0x430 [nf_conntrack] ctnetlink_create_conntrack+0x3cd/0x4e0 [nf_conntrack_netlink] ctnetlink_new_conntrack+0x1c0/0x450 [nf_conntrack_netlink] nfnetlink_rcv_msg+0x277/0x2f0 [nfnetlink] netlink_rcv_skb+0x50/0x100 nfnetlink_rcv+0x65/0x144 [nfnetlink] netlink_unicast+0x1ae/0x290 netlink_sendmsg+0x257/0x4f0 sock_sendmsg+0x5f/0x70 This patch is to fix it by changing to use NF_CT_STAT_INC_ATOMIC() for nf_ct_ext_valid_pre/post() check in nf_conntrack_hash_check_insert(), as well as nf_ct_ext_valid_post() in __nf_conntrack_confirm(). Note that nf_ct_ext_valid_pre() check in __nf_conntrack_confirm() is safe to use NF_CT_STAT_INC(), as it's under local_bh_disable().

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: fix using __this_cpu_add in preemptible Currently in nf_conntrack_hash_check_insert(), when it fails in nf_ct_ext_valid_pre/post(), NF_CT_STAT_INC() will be called in the preemptible context, a call trace can be triggered: BUG: using __this_cpu_add() in preemptible [00000000] code: conntrack/1636 caller is nf_conntrack_hash_check_insert+0x45/0x430 [nf_conntrack] Call Trace: <TASK> dump_stack_lvl+0x33/0x46 check_preemption_disabled+0xc3/0xf0 nf_conntrack_hash_check_insert+0x45/0x430 [nf_conntrack] ctnetlink_create_conntrack+0x3cd/0x4e0 [nf_conntrack_netlink] ctnetlink_new_conntrack+0x1c0/0x450 [nf_conntrack_netlink] nfnetlink_rcv_msg+0x277/0x2f0 [nfnetlink] netlink_rcv_skb+0x50/0x100 nfnetlink_rcv+0x65/0x144 [nfnetlink] netlink_unicast+0x1ae/0x290 netlink_sendmsg+0x257/0x4f0 sock_sendmsg+0x5f/0x70 This patch is to fix it by changing to use NF_CT_STAT_INC_ATOMIC() for nf_ct_ext_valid_pre/post() check in nf_conntrack_hash_check_insert(), as well as nf_ct_ext_valid_post() in __nf_conntrack_confirm(). Note that nf_ct_ext_valid_pre() check in __nf_conntrack_confirm() is safe to use NF_CT_STAT_INC(), as it's under local_bh_disable().

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
local access → vulnerable operation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration.
CWE not yet assigned
CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-W-2024-3251Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Ein Angreifer kann mehrere Schwachstellen in Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen oder andere, nicht näher bekannte Auswirkungen zu erzielen..

Official advisory
CERT-FR · French · CERTFR-2025-AVI-1057Multiples vulnérabilités dans les produits VMware

d?id=CVE-2022-48942 Référence CVE CVE-2022-48944 https://www.cve.org/CVERecord?id=CVE-2022-48944 Référence CVE CVE-2022-48946 https://www.cve.org/CVERecord?id=CVE-2022-48946 Référence CVE CVE-2022-48951 https://www.cve.org/CVERecord?id=CVE-2022-48951 Référence CVE CVE-2022-48953 https://www.cve.org/CVERecord?id=CVE-2022-48953 Référence CVE CVE-2022-48963 https://www.cve.org/CVERecord?id=CVE-2022-48963 Référence CVE CVE-2022-48969 https://www.cve.org/CVERecord?id=CVE-2022-48969 Référence CVE CVE-2022-48971 https://www.cve.org/CVERecord?id=CVE-2022-48971 Référence CVE CVE-2022-48972 https://www.cve.org/CVERecord?id=CVE-2022-48972 Référence CVE CVE-2022-48974 https://www.cve.org/CVERecord?id=CVE-2022-48974 Référence CVE CVE-2022-48976 https://www.cve.org/CVERecord?id=CVE-2022-48976 Référence CVE CVE-2022-48978 https://www.cve.org/CVERecord?id=CVE-2022-48978 Référence CVE CVE-2022-48981 https://www.cve.org/CVERecord?id=CVE-2022-48981 Référence CVE CVE-2022-48982 https://www.cve.org/CVERecord?id=CVE-2022-48982 Référence CVE CVE-2022-48983 https://www.cve.org/CVERecord?id=CVE-2022-48983 Référence CVE CVE-2022-48984 https://www.cve.org/CVERecord?id=CVE-2022-48984 Référence CVE CVE-2022-48985 https://www.cve.org/CVERecord?id=CVE-2022-48985 Référence CVE CVE-2022-48986 https://www.cve.org/CVERecord?id=

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
c56716c69ce1ac320432fb1ea5654196ba24d2f8 < d9bf1138a5db419db13bd9fcd3a7178d6bb20f7c; c56716c69ce1ac320432fb1ea5654196ba24d2f8 < 9464d0b68f11a9bc768370c3260ec02b3550447b; 5.19
Fixed
< 5.19; 6.0.13 ≤ 6.0.*; 6.1 ≤ *
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 21 Oct 2024 · Last source change 11 May 2026, 18:50 UTC · CWE not yet assigned

CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2022-53853
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceUnavailable
NVD statusNVD enriched

Missing structured fields: CWE classification. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2022-53853↗CVE authority or vendor reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2022-48974 · cve.blacktree.nl