CVE-2026-63903: USB: serial: belkin_sa: validate interrupt status length

High 7.1 EPSS 0.2% Linux kernel

In the Linux kernel, the following vulnerability has been resolved: USB: serial: belkin_sa: validate interrupt status length The Belkin interrupt callback treats interrupt data as a four-byte status report and reads LSR/MSR fields at offsets 2 and 3. The interrupt-in buffer length is derived from endpoint wMaxPacketSize, and short interrupt transfers may complete successfully with a smaller actual_length. Check the completed interrupt packet length before parsing status fields so short interrupt endpoints and short successful packets are ignored instead of causing out-of-bounds or stale status-byte reads. KASAN report as below: BUG: KASAN: slab-out-of-bounds in belkin_sa_read_int_callback() Read of size 1 Call trace: belkin_sa_read_int_callback() (drivers/usb/serial/belkin_sa.c:202) __usb_hcd_giveback_urb() (drivers/usb/core/hcd.c:1630) dummy_timer() (?:?)

What do these terms mean? CVE · CVSS score · exploited (KEV) · EPSS · backported fix · all terms

What to do now

  1. Check whether you run Linux kernel and which version (commands below).
  2. Install the fixed version for your system: see “Patch it” below.
  3. Reboot into the new kernel (uname -r to confirm); live patching (kpatch, Ubuntu Livepatch, SUSE kGraft/klp) can defer the reboot for some CVEs

Affected and fixed versions

Affected:

Patch it

Use the commands for your system. Distribution packages often keep an older version number with the fix backported, so compare with the fixed package versions in the table below, not only with the upstream version.

Debian
sudo apt update
sudo apt install --only-upgrade linux-image-amd64
Ubuntu
sudo apt update
sudo apt install --only-upgrade linux-image-generic (or the installed flavour: linux-image-aws, -azure, -gcp, -virtual)
RHEL, AlmaLinux, Rocky, Oracle
sudo dnf upgrade --refresh kernel
Fedora
sudo dnf upgrade --refresh kernel
SUSE / openSUSE
sudo zypper refresh
sudo zypper update kernel-default
Amazon Linux
sudo dnf upgrade --releasever=latest kernel kernel6.12
Arch Linux
sudo pacman -Syu
Alpine
apk update && apk upgrade linux-lts linux-virt
FreeBSD
not Linux

General update steps for every system are on the Linux and Unix & BSD pages; after updating, see which services to restart.

Fix status in Linux distributions

ReleasePackageStatusFixed version / advisory
Debian 12linuxfixed6.1.176-1
Debian 13linuxfixed6.12.94-1
Debian testinglinuxfixed7.0.12-1
Red Hat Enterprise Linux 9kernelfix deferred
Red Hat Enterprise Linux 9kernel-rtfix deferred
Red Hat Enterprise Linux 8kernelfix deferred
Red Hat Enterprise Linux 8kernel-rtfix deferred
Red Hat Enterprise Linux 7kernelfix deferred
Red Hat Enterprise Linux 7kernel-rtfix deferred
Red Hat Enterprise Linux 6kernelout of support scope
Red Hat Enterprise Linux 10kernelfix deferred

From the Debian security tracker, Ubuntu CVE tracker and Red Hat Security Data API, refreshed every few hours.

Sources

Page generated automatically from official sources on 2026-11-03 18:05 UTC. Always confirm with your vendor's advisory.