CVE-2026-80795

What the bug is

nci_target_auto_activated() appends a target to the fixed-size array ndev->targets[NCI_MAX_DISCOVERED_TARGETS] and increments ndev->n_targets without first checking the array is full; unlike its sibling nci_add_new_target(), which bails out when n_targets already equals NCI_MAX_DISCOVERED_TARGETS. ndev->n_targets is only cleared by nci_clear_target_list(), so an NFCC that repeatedly re-runs discovery (RF_DISCOVER_RSP, which re-enters NCI_DISCOVERY without clearing the target list) and reports an auto-activated target (RF_INTF_ACTIVATED_NTF) drives n_targets past the limit. The append then writes a struct nfc_target past the end of the array (a slab out-of-bounds write), and nfc_targets_found() goes on to walk the array with the inflated count: BUG: KASAN: slab-out-of-bounds in nci_add_new_protocol+0x94/0x2ac [nci] Write of size 2 at addr ffff0000c7299a18 by task kworker/u8:0/12 Workqueue: nfc0_nci_rx_wq nci_rx_work [nci] Call trace: nci_add_new_protocol+0x94/0x2ac [nci] nci_ntf_packet+0xddc/0x11a0 [nci] nci_rx_work+0x15c/0x1e0 [nci] process_one_work+0x2dc/0x500 worker_thread+0x240/0x460 kthread+0x1c0/0x1d0 ret_from_fork+0x10/0x20 The buggy address belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1024 bytes to the right of allocated 1560-byte region [ffff0000c7299000, ffff0000c7299618) Guard nci_target_auto_activated() with the same check used by nci_add_new_target().

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

net/nfc/nci/ntf.c

What this is

NFC SUBSYSTEMMAINTAINERS section matched on net/nfc/ · oe-linux-nfc@lists.linux.dev · Maintained

Kernel module

nci

Check it on the machine

grep -wE 'CONFIG_NFC|CONFIG_NFC_NCI' /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w nci

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookworm, trixie, forky, sid, bookworm · linux-6.12Mnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

a module where it is built at all; some flavours do not build it

Build switches

CONFIG_NFC, CONFIG_NFC_NCI

Reads as

all on means the file is compiled; any one off means it is not.

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-09-04 (44 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.24%, higher than 14.4% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

net/nfc

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
3.4	5.10.267	0dc59de0075f
3.4	5.15.218	94530ffabfca
3.4	6.1.185	afd8605fb43b
3.4	6.6.154	24761d3a5f69
3.4	6.12.106	50e87e1c0e18
3.4	6.18.47	2f08dbce3b37
3.4	7.1.11	d7083f41c21b
3.4	7.2.1	129032c0616d
3.4	7.3	ac200079db50

Debian advisories