CVE-2026-31623 PUBLISHED

net: usb: cdc-phonet: fix skb frags[] overflow in rx_complete()

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

In the Linux kernel, the following vulnerability has been resolved:

net: usb: cdc-phonet: fix skb frags[] overflow in rx_complete()

A malicious USB device claiming to be a CDC Phonet modem can overflow the skb_shared_info->frags[] array by sending an unbounded sequence of full-page bulk transfers.

Drop the skb and increment the length error when the frag limit is reached. This matches the same fix that commit f0813bcd2d9d ("net: wwan: t7xx: fix potential skb->frags overflow in RX path") did for the t7xx driver.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to a23b1b1aaf41e174181d5853a70e65d4d01e648c (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to c183d5775129a0a7495bd61a6e57ec230dcf01e5 (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to ebf75c6301c4972a87542ebf2d994c6391eb5d46 (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 9989938d13cc5ba8447eeed5a61acfcf61bc6801 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • unaffected from 6.12.83 to 6.12.* (incl.)
  • unaffected from 6.18.24 to 6.18.* (incl.)
  • unaffected from 6.19.14 to 6.19.* (incl.)
  • unaffected from 7.0.1 to 7.0.* (incl.)

References