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NVD / CVE Program· CNA Linux

CVE-2025-21826: netfilter: nf_tables: reject mismatching sum of field_len with set key length

MediumCVSS 5.5 · v3.1—No exploit Fix available

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: 0.20% (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 1b9335a8000fb70742f7db10af314104b6ace220, 2ac254343d3cf228ae0738b2615fedf85d000752, 49b7182b97bafbd5645414aff054b4a65d05823d.
  • Severity is disputed: the assigning authority (CNA) scores it 7.8, NVD 5.5.

Low priority for now. Upgrade to Linux Linux 1b9335a8000fb70742f7db10af314104b6ace220, 2ac254343d3cf228ae0738b2615fedf85d000752, 49b7182b97bafbd5645414aff054b4a65d05823d 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: nf_tables: reject mismatching sum of field_len with set key length The field length description provides the length of each separated key field in the concatenation, each field gets rounded up to 32-bits to calculate the pipapo rule width from pipapo_init(). The set key length provides the total size of the key aligned to 32-bits. Register-based arithmetics still allows for combining mismatching set key length and field length description, eg. set key length 10 and field description [ 5, 4 ] leading to pipapo width of 12.

Published
Mar 6, 2025
Updated
Oct 15, 2026
EPSS
0.2% · 9th percentile
CWE
—

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 · 0.2%

CNA vs NVD score

NVD
5.5
CNA · Linux
7.8
2.3 point gap

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

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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

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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 kernel5.10.209 and later · before 5.10.235
  • linux linux kernel5.15.148 and later · before 5.15.179
  • linux linux kernel6.1.75 and later · before 6.1.129
  • linux linux kernel6.6.14 and later · before 6.6.76
  • linux linux kernel6.7.2 and later · before 6.12.13
  • linux linux kernel6.13 and later · before 6.13.2

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

    • ff67e3e488090908dc015ba04d7407d8bd467f7e, 6.8affected
    • 2d4c0798a1ef8db15b3277697ac2def4eda42312 and later · before 6b467c8feac759f4c5c86d708beca2aa2b29584faffected · git
    • 77be8c495a3f841e88b46508cc20d3d7d3289da3 and later · before 5083a7ae45003456c253e981b30a43f71230b4a3affected · git
    • 9cb084df01e198119de477ac691d682fb01e80f3 and later · before 2ac254343d3cf228ae0738b2615fedf85d000752affected · git
    • dc45bb00e66a33de1abb29e3d587880e1d4d9a7e and later · before 82e491e085719068179ff6a5466b7387cc4bbf32affected · git
    • 3ce67e3793f48c1b9635beb9bb71116ca1e51b58 and later · before 49b7182b97bafbd5645414aff054b4a65d05823daffected · git
    • 3ce67e3793f48c1b9635beb9bb71116ca1e51b58 and later · before ab50d0eff4a939d20c37721fd9766347efcdb6f6affected · git
    • 3ce67e3793f48c1b9635beb9bb71116ca1e51b58 and later · before 1b9335a8000fb70742f7db10af314104b6ace220affected · git
    • 5.10.209 and later · before 5.10.235affected · semver
    • 5.15.148 and later · before 5.15.179affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.129-16.1.129-1
Debian:13linuxbefore 6.12.13-16.12.13-1
Red Hat:rhel_eus:9.6::appstreamkernel-64k-debug-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-64k-debug-develbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-64k-debug-devel-matchedbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-64k-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-64k-develbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-64k-devel-matchedbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-debug-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-debug-develbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-debug-devel-matchedbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-debuginfo-common-aarch64before 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-debuginfo-common-ppc64lebefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-debuginfo-common-s390xbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-debuginfo-common-x86_64before 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-develbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-devel-matchedbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-docbefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-rt-64k-debug-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-rt-64k-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-rt-debug-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-rt-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6
Red Hat:rhel_eus:9.6::appstreamkernel-tools-debuginfobefore 0:5.14.0-570.142.1.el9_60:5.14.0-570.142.1.el9_6

+69

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-2024-58073Mar 6, 2025 · drm/msm/dpu: check dpu_plane_atomic_print_state() for valid sspp
    22Monitor
  • ← EarlierCVE-2024-58075Mar 6, 2025 · crypto: tegra - do not transfer req when tegra init fails
    22Monitor
  • Later →CVE-2025-21828Mar 6, 2025 · wifi: mac80211: don't flush non-uploaded STAs
    22Monitor

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 Linux1b9335a8000fb70742f7db10af314104b6ace220Vendor (CNA)
Linux Linux2ac254343d3cf228ae0738b2615fedf85d000752Vendor (CNA)
Linux Linux49b7182b97bafbd5645414aff054b4a65d05823dVendor (CNA)
Linux Linux5.10.235Vendor (CNA)
Linux Linux5.15.179Vendor (CNA)
Linux Linux5083a7ae45003456c253e981b30a43f71230b4a3Vendor (CNA)
Linux Linux6.1.129Vendor (CNA)
Linux Linux6.6.76Vendor (CNA)
Linux Linux6.8Vendor (CNA)
Linux Linux6b467c8feac759f4c5c86d708beca2aa2b29584fVendor (CNA)
Linux Linux82e491e085719068179ff6a5466b7387cc4bbf32Vendor (CNA)
Linux Linuxab50d0eff4a939d20c37721fd9766347efcdb6f6Vendor (CNA)
debian:linux6.1.129-1 · Debian:12Package registry (OSV)
red hat:kernel-64k-debug-debuginfo0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-64k-debug-devel-matched0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-64k-debuginfo0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-64k-devel0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-64k-devel-matched0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-debug-debuginfo0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-debug-devel0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-debug-devel-matched0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-debuginfo0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-debuginfo-common-aarch640:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage registry (OSV)
red hat:kernel-debuginfo-common-ppc64le0:5.14.0-570.142.1.el9_6 · Red Hat:rhel_eus:9.6::appstreamPackage 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).

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)

—

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 (10 more)

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

All records