CVE-2026-80794 nfc: nci: fix uninit-value in the RF discover/activated NTF handlers
An attacker with local NFC access can trigger uninitialized memory disclosure in the Linux kernel NFC driver, potentially leaking sensitive kernel data to user space.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80794?
CVE-2026-80794 is a vulnerability in Linux, published on 4 Sep 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:
nfc: nci: fix uninit-value in the RF discover/activated NTF handlers
nci_rf_discover_ntf_packet() and nci_rf_intf_activated_ntf_packet() each parse a notification into an on-stack struct (nci_rf_discover_ntf / nci_rf_intf_activated_ntf) that is not initialised. The RF technology-specific parameters are only extracted when rf_tech_specific_params_len is non-zero, so a notification that reports a zero length leaves the rf_tech_specific_params union uninitialised - and both handlers then pass it to nci_add_new_protocol(), which reads it:
- discover: nci_add_new_target() -> nci_add_new_protocol(); - activated: nci_target_auto_activated() -> nci_add_new_protocol().
nci_add_new_protocol() uses nfca_poll->nfcid1_len as both a branch condition and a memcpy() length and copies nfcid1/sens_res/sel_res into ndev->targets, which is later exposed to user space via NFC_CMD_GET_TARGET.
BUG: KMSAN: uninit-value in nci_add_new_protocol+0x624/0x6c0 nci_add_new_protocol+0x624/0x6c0 nci_ntf_packet+0x25b2/0x3c30 nci_rx_work+0x318/0x5d0 process_scheduled_works+0x84b/0x17a0 worker_thread+0xc10/0x11b0 kthread+0x376/0x500 Local variable ntf.i created at: nci_ntf_packet+0xbc2/0x3c30
Zero-initialise both on-stack notifications so the union reads back as zero when no technology-specific parameters are present.
Which versions are affected by CVE-2026-80794?
How do I fix CVE-2026-80794?
Apply the vendor's patch.
Is CVE-2026-80794 being exploited?
There is no known exploitation of CVE-2026-80794 in the wild and no public exploit code.
Sources
Also known as AZL-99497, BELL-CVE-2026-80794, DEBIAN-CVE-2026-80794, GHSA-p4rx-vcw4-7733, UBUNTU-CVE-2026-80794.