CVE-2026-80575 Input: cs40l50-vibra - validate custom data from user space
A local attacker can cause a kernel crash by providing invalid custom data lengths to the cs40l50-vibra input driver.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80575?
CVE-2026-80575 is a high-severity vulnerability in Linux, published on 26 Aug 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:
Input: cs40l50-vibra - validate custom data from user space
cs40l50_add() copies the custom data of an FF_PERIODIC/FF_CUSTOM effect straight from the ff_effect the user passed to EVIOCSFF, without requiring it to hold anything:
work_data.custom_data = memdup_array_user(periodic->custom_data, periodic->custom_len, sizeof(s16)); work_data.custom_len = periodic->custom_len;
The driver then reads two words out of that buffer: custom_data[0] as the waveform bank in cs40l50_effect_bank_set(), and custom_data[1] as the index within the bank in cs40l50_effect_index_set(). Neither read is covered by a length check, and custom_len is fully user controlled:
- custom_len == 0 makes memdup_array_user() call memdup_user() with a length of zero, which returns ZERO_SIZE_PTR rather than an error, so custom_data[0] dereferences it.
- custom_len == 1 allocates two bytes. A bank of ROM or RAM keeps effect->type out of the OWT case, and custom_data[1] is then read one word past the allocation.
The bank value itself is also mishandled. It is masked with CS40L50_CUSTOM_DATA_MASK (0xffff) but stored in an s16, so a custom_data[0] of 0x8000 or above wraps to a negative value that passes the "bank_type >= CS40L50_WVFRM_BANK_NUM" test. cs40l50_effect_index_set() indexes vib->dsp.banks[] with it before the switch statement's default case gets a chance to reject it:
base_index = vib->dsp.banks[effect->type].base_index; max_index = vib->dsp.banks[effect->type].max_index;
Require the two words the driver reads to be present, and hold the masked bank in a u32 so the existing upper-bound test covers the whole range. The da7280 haptic driver already range checks custom_len this way.
Which versions are affected by CVE-2026-80575?
How do I fix CVE-2026-80575?
Apply the vendor's patch.
Is CVE-2026-80575 being exploited?
There is no known exploitation of CVE-2026-80575 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80575, DEBIAN-CVE-2026-80575, GHSA-6c2r-6hqv-3xph, UBUNTU-CVE-2026-80575.