CVE-2026-23353 ice: fix crash in ethtool offline loopback test

Medium 5.5 Published 25 Mar 2026 Updated 26 Oct 2026

A local attacker can crash the Linux kernel by triggering a NULL pointer dereference in the ice driver during an ethtool loopback test.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2026-23353?

CVE-2026-23353 is a medium-severity vulnerability in Linux kernel, published on 25 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

ice: fix crash in ethtool offline loopback test

Since the conversion of ice to page pool, the ethtool loopback test crashes:

BUG: kernel NULL pointer dereference, address: 000000000000000c #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 1100f1067 P4D 0 Oops: Oops: 0002 [#1] SMP NOPTI CPU: 23 UID: 0 PID: 5904 Comm: ethtool Kdump: loaded Not tainted 6.19.0-0.rc7.260128g1f97d9dcf5364.49.eln154.x86_64 #1 PREEMPT(lazy) Hardware name: [...] RIP: 0010:ice_alloc_rx_bufs+0x1cd/0x310 [ice] Code: 83 6c 24 30 01 66 41 89 47 08 0f 84 c0 00 00 00 41 0f b7 dc 48 8b 44 24 18 48 c1 e3 04 41 bb 00 10 00 00 48 8d 2c 18 8b 04 24 <89> 45 0c 41 8b 4d 00 49 d3 e3 44 3b 5c 24 24 0f 83 ac fe ff ff 44 RSP: 0018:ff7894738aa1f768 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000700 RDI: 0000000000000000 RBP: 0000000000000000 R08: ff16dcae79880200 R09: 0000000000000019 R10: 0000000000000001 R11: 0000000000001000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ff16dcae6c670000 FS: 00007fcf428850c0(0000) GS:ff16dcb149710000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000000c CR3: 0000000121227005 CR4: 0000000000773ef0 PKRU: 55555554 Call Trace: <TASK> ice_vsi_cfg_rxq+0xca/0x460 [ice] ice_vsi_cfg_rxqs+0x54/0x70 [ice] ice_loopback_test+0xa9/0x520 [ice] ice_self_test+0x1b9/0x280 [ice] ethtool_self_test+0xe5/0x200 __dev_ethtool+0x1106/0x1a90 dev_ethtool+0xbe/0x1a0 dev_ioctl+0x258/0x4c0 sock_do_ioctl+0xe3/0x130 __x64_sys_ioctl+0xb9/0x100 do_syscall_64+0x7c/0x700 entry_SYSCALL_64_after_hwframe+0x76/0x7e [...]

It crashes because we have not initialized libeth for the rx ring.

Fix it by treating ICE_VSI_LB VSIs slightly more like normal PF VSIs and letting them have a q_vector. It's just a dummy, because the loopback test does not use interrupts, but it contains a napi struct that can be passed to libeth_rx_fq_create() called from ice_vsi_cfg_rxq() -> ice_rxq_pp_create().

Weakness: CWE-476

Which versions are affected by CVE-2026-23353?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-23353?

Apply the vendor's patch.

Is CVE-2026-23353 being exploited?

There is no known exploitation of CVE-2026-23353 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-23353, GHSA-xv28-8q23-rhh6, UBUNTU-CVE-2026-23353.