cbcvebase.
CVE-2026-46273
published 2026-06-03

CVE-2026-46273: 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…

PriorityP346high8.6CVSS 3.1
AVNACLPRNUINSCCNINAH
EPSS
0.39%
31.2th percentile
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 ("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).

Affected

18 ranges
VendorProductVersion rangeFixed in
linuxlinux
linuxlinux>= 8641dd85799f85bef5f0d1f87356aaa12cb2195e < 86fc64584811d43c9ccd74447de58620189d8b7786fc64584811d43c9ccd74447de58620189d8b77
linuxlinux>= 8641dd85799f85bef5f0d1f87356aaa12cb2195e < 9a5e984d7af910e46dcbed3ce77873e000a4f77d9a5e984d7af910e46dcbed3ce77873e000a4f77d
linuxlinux>= 8641dd85799f85bef5f0d1f87356aaa12cb2195e < 1cdf5dbcec988d06f5f720bdf89e91073f77fa101cdf5dbcec988d06f5f720bdf89e91073f77fa10
linuxlinux>= 8641dd85799f85bef5f0d1f87356aaa12cb2195e < 82bc89fbb82d9396fb4eaee8720ea85e2e78795782bc89fbb82d9396fb4eaee8720ea85e2e787957
linuxlinux>= 8641dd85799f85bef5f0d1f87356aaa12cb2195e < db8012c631cb845e9ae2b4b531e17d86c9519755db8012c631cb845e9ae2b4b531e17d86c9519755
linuxlinux>= 8641dd85799f85bef5f0d1f87356aaa12cb2195e < c1f261863e65b508f37416dfbc5c5d911c9b9233c1f261863e65b508f37416dfbc5c5d911c9b9233
linuxlinux>= 8641dd85799f85bef5f0d1f87356aaa12cb2195e < 3af24f0c4c31f18a4a2d927990759194832bb6e93af24f0c4c31f18a4a2d927990759194832bb6e9
linuxlinux>= 8641dd85799f85bef5f0d1f87356aaa12cb2195e < cc427d24ac6442ffdeafd157a63c7c5b73ed4de4cc427d24ac6442ffdeafd157a63c7c5b73ed4de4
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 4.2 < 5.10.2585.10.258
linuxlinux_kernel>= 5.11 < 5.15.2095.15.209
linuxlinux_kernel>= 5.16 < 6.1.1756.1.175
linuxlinux_kernel>= 6.13 < 6.18.306.18.30
linuxlinux_kernel>= 6.19 < 7.0.77.0.7
linuxlinux_kernel>= 6.2 < 6.6.1406.6.140
linuxlinux_kernel>= 6.7 < 6.12.886.12.88

CVSS provenance

nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
vendor_redhat5.5MEDIUM
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