CVE-2026-46273

Advisory lineage Upstream: 0 Downstream: 20
Analyzed
Published: 03 Jun 2026, 16:19
Last modified:14 Jun 2026, 18:05

Vulnerability Summary

Overall Risk (default)
medium
34/100
CVSS Score
8.6 HIGH
v3.1 (cve.org)
EPSS Score
0.39% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

03 Jun 2026, 16:19
Published
Vulnerability first disclosed
14 Jun 2026, 18:05
Last Modified
Vulnerability information updated

Description

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).

CVSS Metrics

  • v3.1•HIGH•Score: 8.6CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.39%• Percentile: 31%

Affected Systems

  • linux•linux

    ≥ 8641dd85799f85bef5f0d1f87356aaa12cb2195e, < 86fc64584811d43c9ccd74447de58620189d8b77 | ≥ 8641dd85799f85bef5f0d1f87356aaa12cb2195e, < 9a5e984d7af910e46dcbed3ce77873e000a4f77d | ≥ 8641dd85799f85bef5f0d1f87356aaa12cb2195e, < 1cdf5dbcec988d06f5f720bdf89e91073f77fa10 | ≥ 8641dd85799f85bef5f0d1f87356aaa12cb2195e, < 82bc89fbb82d9396fb4eaee8720ea85e2e787957 | ≥ 8641dd85799f85bef5f0d1f87356aaa12cb2195e, < db8012c631cb845e9ae2b4b531e17d86c9519755 | ≥ 8641dd85799f85bef5f0d1f87356aaa12cb2195e, < c1f261863e65b508f37416dfbc5c5d911c9b9233 | ≥ 8641dd85799f85bef5f0d1f87356aaa12cb2195e, < 3af24f0c4c31f18a4a2d927990759194832bb6e9 | ≥ 8641dd85799f85bef5f0d1f87356aaa12cb2195e, < cc427d24ac6442ffdeafd157a63c7c5b73ed4de4 | 4.2

  • linux•linux kernel

    ≥ 4.2, < 5.10.258 | ≥ 5.11, < 5.15.209 | ≥ 5.16, < 6.1.175 | ≥ 6.2, < 6.6.140 | ≥ 6.7, < 6.12.88 | ≥ 6.13, < 6.18.30 | ≥ 6.19, < 7.0.7 | 7.1:rc1

References (8)