CVE-2026-31660 nfc: pn533: allocate rx skb before consuming bytes

What is CVE-2026-31660?

CVE-2026-31660 is a medium-severity vulnerability in Linux kernel, published on 24 Apr 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: pn533: allocate rx skb before consuming bytes

pn532_receive_buf() reports the number of accepted bytes to the serdev core. The current code consumes bytes into recv_skb and may already hand a complete frame to pn533_recv_frame() before allocating a fresh receive buffer.

If that alloc_skb() fails, the callback returns 0 even though it has already consumed bytes, and it leaves recv_skb as NULL for the next receive callback. That breaks the receive_buf() accounting contract and can also lead to a NULL dereference on the next skb_put_u8().

Allocate the receive skb lazily before consuming the next byte instead. If allocation fails, return the number of bytes already accepted.

Which versions are affected by CVE-2026-31660?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-31660?

Apply the vendor's patch.

Is CVE-2026-31660 being exploited?

There is no known exploitation of CVE-2026-31660 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-83681, BELL-CVE-2026-31660, DEBIAN-CVE-2026-31660, GHSA-vh7f-9w49-q39v, ROOT-OS-DEBIAN-11-CVE-2026-31660, ROOT-OS-DEBIAN-12-CVE-2026-31660 and 3 more.