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NVD / CVE Program· CNA Linux

CVE-2026-43451: netfilter: nfnetlink_queue: fix entry leak in bridge verdict error path

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.12% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 0b18d1b834ab5a5009be70b530f978d7989e445b, 208669df703a25a601f45822b10c413f258bf275, 47b1c5d1b0944aa88299f55a846fabaefc756982.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 0b18d1b834ab5a5009be70b530f978d7989e445b, 208669df703a25a601f45822b10c413f258bf275, 47b1c5d1b0944aa88299f55a846fabaefc756982 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: fix entry leak in bridge verdict error path nfqnl_recv_verdict() calls find_dequeue_entry() to remove the queue entry from the queue data structures, taking ownership of the entry. For PF_BRIDGE packets, it then calls nfqa_parse_bridge() to parse VLAN attributes. If nfqa_parse_bridge() returns an error (e.g. NFQA_VLAN present but NFQA_VLAN_TCI missing), the function returns immediately without freeing the dequeued entry or its sk_buff. This leaks the nf_queue_entry, its associated sk_buff, and all held references (net_device refcounts, struct net refcount). Repeated triggering exhausts kernel memory. Fix this by dropping the entry via nfqnl_reinject() with NF_DROP verdict on the error path, consistent with other error handling in this file.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
May 8, 2026
Updated
Jun 17, 2026
EPSS
0.1% · 2th percentile

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel4.7 and later · before 5.10.253
  • linux linux kernel5.11 and later · before 5.15.203
  • linux linux kernel5.16 and later · before 6.1.167
  • linux linux kernel6.2 and later · before 6.6.130
  • linux linux kernel6.7 and later · before 6.12.78
  • linux linux kernel6.13 and later · before 6.18.19
  • linux linux kernel6.19 and later · before 6.19.9
  • linux linux kernel7.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 4.7affected
    • 8d45ff22f1b43249f0cf1baafe0262ca10d1666e and later · before a907bea273b60d3e604ec4e8e1f6c49954805794affected · git
    • 8d45ff22f1b43249f0cf1baafe0262ca10d1666e and later · before 0b18d1b834ab5a5009be70b530f978d7989e445baffected · git
    • 8d45ff22f1b43249f0cf1baafe0262ca10d1666e and later · before b38d2b4603fd3dda24eb8b3dd81c18a0930be97baffected · git
    • 8d45ff22f1b43249f0cf1baafe0262ca10d1666e and later · before 47b1c5d1b0944aa88299f55a846fabaefc756982affected · git
    • 8d45ff22f1b43249f0cf1baafe0262ca10d1666e and later · before cf4a4df38d1747e06fc54f9879bd7a6f4178032faffected · git
    • 8d45ff22f1b43249f0cf1baafe0262ca10d1666e and later · before 9853d94b82d303fc4ac37d592a23a154096ecd41affected · git
    • 8d45ff22f1b43249f0cf1baafe0262ca10d1666e and later · before 208669df703a25a601f45822b10c413f258bf275affected · git
    • 8d45ff22f1b43249f0cf1baafe0262ca10d1666e and later · before f1ba83755d81c6fc66ac7acd723d238f974091e9affected · git
    • before 4.7not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.170-16.1.170-1
Debian:13linuxbefore 6.12.85-16.12.85-1
Debian:14linuxbefore 6.19.10-16.19.10-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2026-43449May 8, 2026 · nvme-pci: Fix slab-out-of-bounds in nvme_dbbuf_set
    28Monitor
  • ← EarlierCVE-2026-43450May 8, 2026 · netfilter: nfnetlink_cthelper: fix OOB read in nfnl_cthelper_dump_table()
    28Monitor
  • Later →CVE-2026-43453May 8, 2026 · netfilter: nft_set_pipapo: fix stack out-of-bounds read in pipapo_drop()
    28Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux0b18d1b834ab5a5009be70b530f978d7989e445bVendor (CNA)
Linux Linux208669df703a25a601f45822b10c413f258bf275Vendor (CNA)
Linux Linux47b1c5d1b0944aa88299f55a846fabaefc756982Vendor (CNA)
Linux Linux9853d94b82d303fc4ac37d592a23a154096ecd41Vendor (CNA)
Linux Linuxa907bea273b60d3e604ec4e8e1f6c49954805794Vendor (CNA)
Linux Linuxb38d2b4603fd3dda24eb8b3dd81c18a0930be97bVendor (CNA)
Linux Linuxcf4a4df38d1747e06fc54f9879bd7a6f4178032fVendor (CNA)
Linux Linuxf1ba83755d81c6fc66ac7acd723d238f974091e9Vendor (CNA)
debian:linux6.1.170-1 · Debian:12Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-401 · Missing Release of Memory after Effective Lifetime

CVSS vector

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

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (7 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records