Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2026-46273: ibmveth: Disable GSO for packets with small MSS

Noroxi assessment

Priority: Monitor (action score 34/100)

  • 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: 0.38% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: Linux Linux 1cdf5dbcec988d06f5f720bdf89e91073f77fa10, 3af24f0c4c31f18a4a2d927990759194832bb6e9, 82bc89fbb82d9396fb4eaee8720ea85e2e787957; azl3 kernel 6.6.139.1-1 on Azure Linux 3.0 6.6.141.1-1.

Low priority for now. Upgrade to Linux Linux 1cdf5dbcec988d06f5f720bdf89e91073f77fa10, 3af24f0c4c31f18a4a2d927990759194832bb6e9, 82bc89fbb82d9396fb4eaee8720ea85e2e787957; azl3 kernel 6.6.139.1-1 on Azure Linux 3.0 6.6.141.1-1 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: ibmveth: Disable GSO for packets with small MSS Some physical adapters on Power systems do not support segmentation offload when the MSS is less than 224 bytes. Attempting to send such packets causes the adapter to freeze, stopping all traffic until manually reset. Implement ndo_features_check to disable GSO for packets with small MSS values. The network stack will perform software segmentation instead. The 224-byte minimum matches ibmvnic commit <f10b09ef687f> ("ibmvnic: Enforce stronger sanity checks on GSO packets") which uses the same physical adapters in SEA configurations. The issue occurs specifically when the hardware attempts to perform segmentation (gso_segs > 1) with a small MSS. Single-segment GSO packets (gso_segs == 1) do not trigger the problematic LSO code path and are transmitted normally without segmentation. Add an ndo_features_check callback to disable GSO when MSS < 224 bytes. Also call vlan_features_check() to ensure proper handling of VLAN packets, particularly QinQ (802.1ad) configurations where the hardware parser may not support certain offload features. Validated using iptables to force small MSS values. Without the fix, the adapter freezes. With the fix, packets are segmented in software and transmission succeeds. Comprehensive regression testing completedd (MSS tests, performance, stability).

HighCVSS 8.6 · v3.1—No exploit Fix available
Published
Jun 3, 2026
Updated
Aug 7, 2026
EPSS
0.3% · 33th percentile

Report tools

JSON

Action score

34

Monitor

Low priority for now.

CVSS
34 / 40 · 8.6 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Linux
8.6
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-2026-46273

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

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

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.

We use this product, ask for help

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 kernel4.2 and later · before 5.10.258
  • linux linux kernel5.11 and later · before 5.15.209
  • linux linux kernel5.16 and later · before 6.1.175
  • linux linux kernel6.2 and later · before 6.6.140
  • linux linux kernel6.7 and later · before 6.12.88
  • linux linux kernel6.13 and later · before 6.18.30
  • linux linux kernel6.19 and later · before 7.0.7
  • 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

    • 4.2affected
    • 8641dd85799f85bef5f0d1f87356aaa12cb2195e and later · before 86fc64584811d43c9ccd74447de58620189d8b77affected · git
    • 8641dd85799f85bef5f0d1f87356aaa12cb2195e and later · before 9a5e984d7af910e46dcbed3ce77873e000a4f77daffected · git
    • 8641dd85799f85bef5f0d1f87356aaa12cb2195e and later · before 1cdf5dbcec988d06f5f720bdf89e91073f77fa10affected · git
    • 8641dd85799f85bef5f0d1f87356aaa12cb2195e and later · before 82bc89fbb82d9396fb4eaee8720ea85e2e787957affected · git
    • 8641dd85799f85bef5f0d1f87356aaa12cb2195e and later · before db8012c631cb845e9ae2b4b531e17d86c9519755affected · git
    • 8641dd85799f85bef5f0d1f87356aaa12cb2195e and later · before c1f261863e65b508f37416dfbc5c5d911c9b9233affected · git
    • 8641dd85799f85bef5f0d1f87356aaa12cb2195e and later · before 3af24f0c4c31f18a4a2d927990759194832bb6e9affected · git
    • 8641dd85799f85bef5f0d1f87356aaa12cb2195e and later · before cc427d24ac6442ffdeafd157a63c7c5b73ed4de4affected · git
    • before 4.2not 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 6.12.88-16.12.88-1
Debian:14linuxbefore 7.0.7-17.0.7-1
openSUSE:Tumbleweedkernel-sourcebefore 7.0.12-1.17.0.12-1.1

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-2026-46269Jun 3, 2026 · pinctrl: canaan: k230: Fix NULL pointer dereference when parsing devicetree
    22Monitor
  • ← EarlierCVE-2026-46270Jun 3, 2026 · power: supply: rt9455: Fix use-after-free in power_supply_changed()
    33Monitor
  • Later →CVE-2025-71313Jun 3, 2026 · PCI: endpoint: Add missing NULL check for alloc_workqueue()
    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 Linux1cdf5dbcec988d06f5f720bdf89e91073f77fa10Vendor (CNA)
Linux Linux3af24f0c4c31f18a4a2d927990759194832bb6e9Vendor (CNA)
Linux Linux82bc89fbb82d9396fb4eaee8720ea85e2e787957Vendor (CNA)
Linux Linux86fc64584811d43c9ccd74447de58620189d8b77Vendor (CNA)
Linux Linux9a5e984d7af910e46dcbed3ce77873e000a4f77dVendor (CNA)
Linux Linuxc1f261863e65b508f37416dfbc5c5d911c9b9233Vendor (CNA)
Linux Linuxcc427d24ac6442ffdeafd157a63c7c5b73ed4de4Vendor (CNA)
Linux Linuxdb8012c631cb845e9ae2b4b531e17d86c9519755Vendor (CNA)
azl3 kernel 6.6.139.1-1 on Azure Linux 3.06.6.141.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.1.176-1 · Debian:12Package registry (OSV)
opensuse:kernel-source7.0.12-1.1 · openSUSE:TumbleweedPackage 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.

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.

  • CVE-2025-38501291 days apartksmbd: limit repeated connections from clients with the same IP
    31Monitor
  • CVE-2026-458597 days apartnetfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation
    30Monitor
  • CVE-2026-458607 days apartnetfilter: nf_conncount: increase the connection clean up limit to 64
    30Monitor
  • CVE-2026-5318322 days apartmptcp: allow subflow rcv wnd to shrink
    30Monitor
  • CVE-2026-6417546 days apartwifi: iwlwifi: mld: stop TX during firmware restart
    30Monitor
  • CVE-2026-23086119 days apartvsock/virtio: cap TX credit to local buffer size
    22Monitor

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

  • Anyone who can reach it over the internet 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
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Changed
Confidentiality impact
None
Integrity impact
None
Availability impact
High

CVSS vector

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

nvd-secondary

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

ts
function expand(node) {  return node.children.map(expand);}

Fixed

ts
const MAX_DEPTH = 32;function expand(node, depth = 0) {  if (depth > MAX_DEPTH) throw new Error("too deep");  return node.children.map((c) => expand(c, depth + 1));}

Attack context

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

Change log

  1. Fix✗ → ✓

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

References

All records