LiveActive security incident?Get immediate response
CVE Record

CVE-2026-43024: netfilter: nf_tables: reject immediate NF_QUEUE verdict

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: reject immediate NF_QUEUE verdict nft_queue is always used from userspace nftables to deliver the NF_QUEUE verdict. Immediately emitting an NF_QUEUE verdict is never used by the userspace nft tools, so reject immediate NF_QUEUE verdicts. The arp family does not provide queue support, but such an immediate verdict is still reachable. Globally reject NF_QUEUE immediate verdicts to address this issue.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

This Linux kernel issue affects nftables packet-filtering behavior. The kernel now rejects an immediate NF_QUEUE verdict because normal userspace nftables does not use it, and the arp family lacks queue support. Business urgency depends on whether exposed systems run affected kernel builds and permit nftables rule changes.

Executive priority

Track as a targeted kernel maintenance item, not an emergency based on supplied evidence. Prioritize systems where untrusted users, tenants, or management planes could influence nftables configuration.

Technical view

The resolved flaw is in netfilter nf_tables. Immediate NF_QUEUE verdicts were reachable even where queue support was unavailable, including the arp family. Kernel stable commits globally reject immediate NF_QUEUE verdicts, leaving nft_queue as the intended userspace path for NF_QUEUE delivery.

Likely exposure

Exposure is limited to Linux systems running affected kernel versions listed in the CVE source. Risk is most relevant where local privileged or semi-privileged network-filter configuration paths can alter nftables rules. Appliances embedding Linux, including Siemens-listed advisories, should be checked against vendor firmware guidance.

Exploitation context

The bundle does not report CISA KEV listing, active exploitation, public exploit use, CVSS, or CWE data. It only states the kernel behavior was resolved by rejecting immediate NF_QUEUE verdicts. Treat exploitability and impact as not fully characterized from the supplied evidence.

Researcher notes

Key uncertainty is impact: the source states reachability and the corrective rejection logic, but does not define crash, privilege escalation, bypass, or denial-of-service outcome. Avoid assuming exploitability beyond the documented nf_tables immediate NF_QUEUE handling flaw.

Mitigation direction

  • Update affected Linux kernels to vendor-provided fixed releases or backported stable patches.
  • Review Siemens advisories for affected appliance firmware and remediation guidance.
  • Restrict administrative access to nftables and network-filter configuration interfaces.
  • Prioritize internet-facing or multi-tenant Linux systems after vendor exposure confirmation.

Validation and detection

  • Inventory Linux kernel versions across servers, containers hosts, and appliances.
  • Compare kernel builds against CVE listed affected and unaffected versions.
  • Check whether nftables is enabled and administratively reachable on each host.
  • Verify vendor advisories for Siemens products in your environment.
  • Confirm patched kernels include the referenced stable commits.
Prepared
Confidence
medium
Sources
12

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2026-43024 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
1ADP providers
11Source links

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

siemens-SADPADP container

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinux55a60251fa50d4e68175e36666b536a602ce4f6c, 960cf4f812530f01f6acc6878ceaa5404c06af7b, 8e34430e33b8a80bc014f3efe29cac76bc30a4b4, 6653118b176a00915125521c6572ae8e507621db, f342de4e2f33e0e39165d8639387aa6c19dff660, f342de4e2f33e0e39165d8639387aa6c19dff660, f342de4e2f33e0e39165d8639387aa6c19dff660, f342de4e2f33e0e39165d8639387aa6c19dff660, 8365e9d92b85fda975a5ece7a3a139cb964018c8, 4e66422f1b56149761dc76030e6345d1cca6f869, f05a497e7bc8851eeeb3a58da180ba469efebb05, 5.10.210, 5.15.149, 6.1.76, 6.6.15, 4.19.307, 5.4.269, 6.7.3unaffected
LinuxLinux6.8, 0, 5.10.253, 5.15.203, 6.1.168, 6.6.134, 6.12.81, 6.18.22, 6.19.12, 7.0affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.