CVE-2022-50656 nfc: pn533: Clear nfc_target before being used
A slab-out-of-bounds read in the Linux kernel NFC driver allows attackers to cause a denial of service or read sensitive memory.
- 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-2022-50656?
CVE-2022-50656 is a high-severity memory corruption vulnerability in Linux, published on 9 Dec 2025. 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: pn533: Clear nfc_target before being used
Fix a slab-out-of-bounds read that occurs in nla_put() called from nfc_genl_send_target() when target->sensb_res_len, which is duplicated from an nfc_target in pn533, is too large as the nfc_target is not properly initialized and retains garbage values. Clear nfc_targets with memset() before they are used.
Found by a modified version of syzkaller.
BUG: KASAN: slab-out-of-bounds in nla_put Call Trace: memcpy nla_put nfc_genl_dump_targets genl_lock_dumpit netlink_dump __netlink_dump_start genl_family_rcv_msg_dumpit genl_rcv_msg netlink_rcv_skb genl_rcv netlink_unicast netlink_sendmsg sock_sendmsg ____sys_sendmsg ___sys_sendmsg __sys_sendmsg do_syscall_64
Which versions are affected by CVE-2022-50656?
How do I fix CVE-2022-50656?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2022-50656 being exploited?
There is no known exploitation of CVE-2022-50656 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2022-50656, GHSA-fqj4-9qj3-355r, UBUNTU-CVE-2022-50656.