CVE-2026-31660 PUBLISHED

nfc: pn533: allocate rx skb before consuming bytes

Assigner: Linux
Reserved: 09.03.2026 Published: 24.04.2026 Updated: 24.04.2026

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.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from c656aa4c27b17a8c70da223ed5ab42145800d6b5 to 2ca64fb7e2d2ae14619dd204d4f2f0a601f421fb (excl.)
  • affected from c656aa4c27b17a8c70da223ed5ab42145800d6b5 to 8b71299d587d9e4c830c18afb884c80ddb30ad28 (excl.)
  • affected from c656aa4c27b17a8c70da223ed5ab42145800d6b5 to 16649adc2e19509104245ea1f349b629d858f11f (excl.)
  • affected from c656aa4c27b17a8c70da223ed5ab42145800d6b5 to 07cb6c72e66ba548679f22ac29ad588da8999279 (excl.)
  • affected from c656aa4c27b17a8c70da223ed5ab42145800d6b5 to a9495069b43b8634c1ae0042e888766c34f66637 (excl.)
  • affected from c656aa4c27b17a8c70da223ed5ab42145800d6b5 to 21ae2cda66a55c759607bbf1d23cbaa42019d2de (excl.)
  • affected from c656aa4c27b17a8c70da223ed5ab42145800d6b5 to 7e37da42eda45d7859d9273fc7e225d8df458038 (excl.)
  • affected from c656aa4c27b17a8c70da223ed5ab42145800d6b5 to c71ba669b570c7b3f86ec875be222ea11dacb352 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 5.5 is affected
  • unaffected from 0 to 5.5 (excl.)
  • unaffected from 5.10.253 to 5.10.* (incl.)
  • unaffected from 5.15.203 to 5.15.* (incl.)
  • unaffected from 6.1.169 to 6.1.* (incl.)
  • unaffected from 6.6.135 to 6.6.* (incl.)
  • unaffected from 6.12.82 to 6.12.* (incl.)
  • unaffected from 6.18.23 to 6.18.* (incl.)
  • unaffected from 6.19.13 to 6.19.* (incl.)
  • unaffected from 7.0 to * (incl.)

References