CVE-2026-98770 usb: gadget: midi2: Fix the jack descriptor array sizes
A local attacker with physical access can trigger an out-of-bounds write in the Linux kernel USB MIDI2 gadget driver via configfs, potentially leading to code execution or system crash.
- 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-2026-98770?
CVE-2026-98770 is a memory corruption vulnerability in Linux, published on 18 Oct 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:
usb: gadget: midi2: Fix the jack descriptor array sizes
The jack in/out descriptor arrays in struct f_midi2_usb_config have the size of MAX_CABLES, which look reasonable -- but it turned out to be incorrect. Namely, the entries for those arrays are added from both inputs and outputs, hence for each loop cycle, it adds two, ended up with as twice as the expected size. This inconsistency may result in potential OOB when a large number of jacks are set up via configfs, although the max number of cables (the loop count) is limited to MAX_CABLES.
For addressing it, correct the jack_ins & jack_outs array sizes to twice, MAX_CABLES * 2.
Which versions are affected by CVE-2026-98770?
How do I fix CVE-2026-98770?
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-2026-98770 being exploited?
There is no known exploitation of CVE-2026-98770 in the wild and no public exploit code.
Sources
Also known as AZL-109337, BELL-CVE-2026-98770, DEBIAN-CVE-2026-98770, GHSA-2cr9-h7x6-p393, UBUNTU-CVE-2026-98770.