KEVWire

Security intelligence, with context.

Response snapshot Oct 30, 2026, 22:31 UTC

Back to the wire
Permalink
VulnerabilityCVE-2026-72320

Linux kernel: netfilter: nft_lookup: fix catchall element handling with inverted lookups

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_lookup: fix catchall element handling with inverted lookups nft_lookup_eval() decides whether a lookup matched (found) from the direct set lookup and priv->invert before falling back to the catchall element used by interval sets (e.

At a glance

Exploited
Not known
Severity
9.1 Critical (CVSS 3.1)
Chance of exploitation
0.5% in the next 30 days
Sources
1 source

What to do

Check the vendor advisory for affected versions and fixes.

Read NVD CVE-2026-72320 (opens a new tab)

What happened

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nft_lookup: fix catchall element handling with inverted lookups

nft_lookup_eval() decides whether a lookup matched (found) from the direct set lookup and priv->invert before falling back to the catchall element used by interval sets (e.g. nft_set_rbtree) for the open-ended default range. Since found is never recomputed after ext is replaced by the catchall lookup, inverted lookups (NFT_LOOKUP_F_INV, "!

= @set") can wrongly match or wrongly skip the catchall element, producing the wrong verdict. Fold the catchall lookup into ext before computing found, matching the order already used by nft_objref_map_eval().

Scores and how they were measured

CVSS base severity

9.1

Version 3.1As of

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

Measurement source (opens a new tab)

How bad it is if exploited. Not a prediction of exploitation or proof you are exposed.

EPSS probability

0.5%

Scored Percentile 44.4%

Model and measurement source (opens a new tab)

A model's estimate of exploitation in the next 30 days, not certainty or your own risk.

Related technology

Sources

  1. Primary source

    NVD CVE-2026-72320 (opens a new tab)

    NVD record: description, CVSS (the CNA score is preferred), affected products, and publication date. Not evidence of exploitation.

    Published Checked

  2. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  3. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  4. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  5. Primary source

    FIRST measured EPSS score (opens a new tab)

    Measured EPSS probability and percentile for CVE-2026-72320, scored 2026-10-30. This is a model estimate, not proof of exposure.

    Published Checked

Cite this record

For factual claims, cite the primary sources above; cite KEVWire for its compilation, dates, and classifications.

APA

KEVWire. (2026, October 30). Linux kernel: netfilter: nft_lookup: fix catchall element handling with inverted lookups (CVE-2026-72320). https://kevwire.com/record/CVE-2026-72320

MLA

"Linux kernel: netfilter: nft_lookup: fix catchall element handling with inverted lookups (CVE-2026-72320)." KEVWire, 30 Oct. 2026, kevwire.com/record/CVE-2026-72320.

Chicago

KEVWire. "Linux kernel: netfilter: nft_lookup: fix catchall element handling with inverted lookups (CVE-2026-72320)." Last modified October 30, 2026. https://kevwire.com/record/CVE-2026-72320.

Evidence summary (plain text)

Linux kernel: netfilter: nft_lookup: fix catchall element handling with inverted lookups (Aug 15, 2026).
In the Linux kernel, the following vulnerability has been resolved:

netfilter: nft_lookup: fix catchall element handling with inverted lookups

nft_lookup_eval() decides whether a lookup matched (found) from the
direct set lookup and priv->invert before falling back to the
catchall element used by interval sets (e.g. nft_set_rbtree) for the
open-ended default range. Since found is never recomputed after
ext is replaced by the catchall lookup, inverted lookups
(NFT_LOOKUP_F_INV, "!= @set") can wrongly match or wrongly skip the
catchall element, producing the wrong verdict.
CVSS 9.1 (version 3.1; evidence as of Oct 30, 2026; https://nvd.nist.gov/vuln/detail/CVE-2026-72320).
EPSS 0.5% for the following 30 days, scored Oct 30, 2026 (https://api.first.org/data/v1/epss?cve=CVE-2026-72320&date=2026-10-30).
Sources:
NVD CVE-2026-72320: https://nvd.nist.gov/vuln/detail/CVE-2026-72320
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-30T13:06:45.042Z&lastModEndDate=2026-10-30T14:50:57.069Z&resultsPerPage=500&startIndex=500
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-30T12:22:16.957Z&lastModEndDate=2026-10-30T14:05:57.373Z&resultsPerPage=500&startIndex=500
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-30T11:45:59.009Z&lastModEndDate=2026-10-30T13:20:57.281Z&resultsPerPage=500&startIndex=500
FIRST measured EPSS score: https://api.first.org/data/v1/epss?cve=CVE-2026-72320&date=2026-10-30
Record ID: CVE-2026-72320.
Record origin: Ingested record.
AI evidence: Not assessed.
Known exploitation: Not assessed.
Zero-day status: Not assessed. KEV membership alone does not establish zero-day status.
About this data

This record was ingested from a data source. Retrieved: Oct 30, 2026, 21:01 UTC. Ingestion is not an independent editorial investigation.

NVD status: Received. Publication in the NVD is not evidence of exploitation.

A CISA KEV listing documents known exploitation, not necessarily a zero-day; absence from the catalog does not prove a vulnerability has never been exploited.

Technology tags indicate possible relevance, not verified exposure. Confirm the affected product, version, and configuration against your own inventory; KEVWire does not scan your systems.

A personal reading checklist on this device, not verified remediation.

Record JSON

Your account

Email alerts

Email alerts are coming as part of KEVWire Premium: join the waitlist. To follow your stack today, use its RSS feed, which honors your filters, or connect an AI agent through the API.

Suggest an improvement

Ideas, missing sources, corrections, and bugs are all welcome. No account needed. Suggestions are reviewed by a person before anything changes.

Record details

Record detail