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NVD / CVE Program· CNA Linux

CVE-2026-46322: tun: free page on build_skb failure in tun_xdp_one()

Noroxi assessment

Priority: Monitor (action score 28/100)

  • 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: 0.13% (FIRST EPSS).
  • Someone with local access to the system can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 2638a9c1521905bb5c5d1e95c8fbc09f79148ed7, 26fe549b5192536b6c1c68a2dfdc8c0dcf9fa4a9, 4fefc6156a162a9f50035c12091a5e5130c82c6e; azl3 kernel 6.6.141.1-1 on Azure Linux 3.0 6.6.143.1-1.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 2638a9c1521905bb5c5d1e95c8fbc09f79148ed7, 26fe549b5192536b6c1c68a2dfdc8c0dcf9fa4a9, 4fefc6156a162a9f50035c12091a5e5130c82c6e; azl3 kernel 6.6.141.1-1 on Azure Linux 3.0 6.6.143.1-1 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: tun: free page on build_skb failure in tun_xdp_one() When build_skb() fails in tun_xdp_one(), the function sets ret to -ENOMEM and jumps to the out label, which returns without freeing the page that vhost_net_build_xdp() allocated for the frame. As with the short-frame rejection path, tun_sendmsg() discards the per-buffer error and still returns total_len, so vhost_tx_batch() takes the success path and never frees the page. Each build_skb() failure in a batch leaks one page-frag chunk. Free the page before taking the error path, matching the put_page() the other error exits of tun_xdp_one() already perform.

HighCVSS 7.1 · v3.1—No exploit Fix available
Published
Jun 9, 2026
Updated
Oct 19, 2026
EPSS
0.1% · 2th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Linux
7.1
NVD has not scored this yet; the score shown is the CNA’s.

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

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

Follow CVE-2026-46322

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 kernel4.20 and later · before 5.10.259
  • linux linux kernel5.11 and later · before 5.15.210
  • linux linux kernel5.16 and later · before 6.1.176
  • linux linux kernel6.2 and later · before 6.6.143
  • linux linux kernel6.7 and later · before 6.12.93
  • linux linux kernel6.13 and later · before 6.18.35
  • linux linux kernel6.19 and later · before 7.0.12
  • linux linux kernel7.1

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

    • 4.20affected
    • 043d222f93ab8c76b56a3b315cd8692e35affb6c and later · before 26fe549b5192536b6c1c68a2dfdc8c0dcf9fa4a9affected · git
    • 043d222f93ab8c76b56a3b315cd8692e35affb6c and later · before 793385c154771603b8671dd8338927221e9d8d78affected · git
    • 043d222f93ab8c76b56a3b315cd8692e35affb6c and later · before 2638a9c1521905bb5c5d1e95c8fbc09f79148ed7affected · git
    • 043d222f93ab8c76b56a3b315cd8692e35affb6c and later · before 60d9c0d6cdde5420d6483c921b16fe5465eb5238affected · git
    • 043d222f93ab8c76b56a3b315cd8692e35affb6c and later · before d16e38fac09a47bfcf98c1ad65a1bb53f94540f5affected · git
    • 043d222f93ab8c76b56a3b315cd8692e35affb6c and later · before aa308e9dbb9acb17cacdbbce9e4504f69bac8385affected · git
    • 043d222f93ab8c76b56a3b315cd8692e35affb6c and later · before 4fefc6156a162a9f50035c12091a5e5130c82c6eaffected · git
    • 043d222f93ab8c76b56a3b315cd8692e35affb6c and later · before aa8963fdce667a42fb7f0bdd2909fadcab02f9a8affected · git
    • before 4.20not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.176-16.1.176-1
Debian:13linuxbefore 6.12.94-16.12.94-1
Debian:14linuxbefore 7.0.12-17.0.12-1

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-2026-46320Jun 9, 2026 · tap: free page on error paths in tap_get_user_xdp()
    29Monitor
  • ← EarlierCVE-2026-46321Jun 9, 2026 · tun: free page on short-frame rejection in tun_xdp_one()
    28Monitor
  • Later →CVE-2026-46323Jun 9, 2026 · net: gro: don't merge zcopy skbs
    31Monitor

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 Linux2638a9c1521905bb5c5d1e95c8fbc09f79148ed7Vendor (CNA)
Linux Linux26fe549b5192536b6c1c68a2dfdc8c0dcf9fa4a9Vendor (CNA)
Linux Linux4fefc6156a162a9f50035c12091a5e5130c82c6eVendor (CNA)
Linux Linux60d9c0d6cdde5420d6483c921b16fe5465eb5238Vendor (CNA)
Linux Linux793385c154771603b8671dd8338927221e9d8d78Vendor (CNA)
Linux Linuxaa308e9dbb9acb17cacdbbce9e4504f69bac8385Vendor (CNA)
Linux Linuxaa8963fdce667a42fb7f0bdd2909fadcab02f9a8Vendor (CNA)
Linux Linuxd16e38fac09a47bfcf98c1ad65a1bb53f94540f5Vendor (CNA)
azl3 kernel 6.6.141.1-1 on Azure Linux 3.06.6.143.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.1.176-1 · 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.
  • No account or password is required.
  • 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

Impact can extend beyond the vulnerable component (scope changes).

Attack vector
Local
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Changed
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:N/UI:N/S:C/C:N/I:N/A:H

nvd-secondary

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. SSVC exploitation— → none
  2. Fix✗ → ✓

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

References

Show all references (8 more)

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

All records