CVE-2026-31563
Published: April 24, 2026· Updated: Apr 27, 2026
Official Description
In the Linux kernel, the following vulnerability has been resolved:
net: macb: Use dev_consume_skb_any() to free TX SKBs
The napi_consume_skb() function is not intended to be called in an IRQ
disabled context. However, after commit 6bc8a5098bf4 ("net: macb: Fix
tx_ptr_lock locking"), the freeing of TX SKBs is performed with IRQs
disabled. To resolve the following call trace, use dev_consume_skb_any()
for freeing TX SKBs:
WARNING: kernel/softirq.c:430 at __local_bh_enable_ip+0x174/0x188, CPU#0: ksoftirqd/0/15
Modules linked in:
CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 7.0.0-rc4-next-20260319-yocto-standard-dirty #37 PREEMPT
Hardware name: ZynqMP ZCU102 Rev1.1 (DT)
pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __local_bh_enable_ip+0x174/0x188
lr : local_bh_enable+0x24/0x38
sp : ffff800082b3bb10
x29: ffff800082b3bb10 x28: ffff0008031f3c00 x27: 000000000011ede0
x26: ffff000800a7ff00 x25: ffff800083937ce8 x24: 0000000000017a80
x23: ffff000803243a78 x22: 0000000000000040 x21: 0000000000000000
x20: ffff000800394c80 x19: 0000000000000200 x18: 0000000000000001
x17: 0000000000000001 x16: ffff000803240000 x15: 0000000000000000
x14: ffffffffffffffff x13: 0000000000000028 x12: ffff000800395650
x11: ffff8000821d1528 x10: ffff800081c2bc08 x9 : ffff800081c1e258
x8 : 0000000100000301 x7 : ffff8000810426ec x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000008 x1 : 0000000000000200 x0 : ffff8000810428dc
Call trace:
__local_bh_enable_ip+0x174/0x188 (P)
local_bh_enable+0x24/0x38
skb_attempt_defer_free+0x190/0x1d8
napi_consume_skb+0x58/0x108
macb_tx_poll+0x1a4/0x558
__napi_poll+0x50/0x198
net_rx_action+0x1f4/0x3d8
handle_softirqs+0x16c/0x560
run_ksoftirqd+0x44/0x80
smpboot_thread_fn+0x1d8/0x338
kthread+0x120/0x150
ret_from_fork+0x10/0x20
irq event stamp: 29751
hardirqs last enabled at (29750): [<ffff8000813be184>] _raw_spin_unlock_irqrestore+0x44/0x88
hardirqs last disabled at (29751): [<ffff8000813bdf60>] _raw_spin_lock_irqsave+0x38/0x98
softirqs last enabled at (29150): [<ffff8000800f1aec>] handle_softirqs+0x504/0x560
softirqs last disabled at (29153): [<ffff8000800f2fec>] run_ksoftirqd+0x44/0x80
Technical Analysis
CVE-2026-31563 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (6)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-31563 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts