CVE-2026-64483 ALSA: firewire: isight: bound the sample count to the packet payload
A malicious FireWire device can trigger a buffer overflow in the Linux kernel ALSA iSight driver, 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-2026-64483?
CVE-2026-64483 is a memory corruption vulnerability in Linux, published on 25 Jul 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:
ALSA: firewire: isight: bound the sample count to the packet payload
isight_packet() takes the frame count from the device iso packet and checks it only against the device claimed iso length.
count = be32_to_cpu(payload->sample_count); if (likely(count <= (length - 16) / 4)) isight_samples(isight, payload->samples, count);
length is the iso header data_length. It can be up to 0xffff. So the gate allows a count up to about 16379. isight_samples() then copies count frames out of payload->samples into the PCM DMA buffer.
payload->samples holds only 2 * MAX_FRAMES_PER_PACKET values. The device multiplexes two samples per frame. A count past MAX_FRAMES_PER_PACKET reads past the payload. A count past the buffer size writes past runtime->dma_area. The smallest PCM buffer is larger than MAX_FRAMES_PER_PACKET. Bounding the count to MAX_FRAMES_PER_PACKET keeps both the read and the write in range.
A malicious or faulty Apple iSight on the FireWire bus reaches this during a normal capture.
Add the MAX_FRAMES_PER_PACKET bound to the gate.
Which versions are affected by CVE-2026-64483?
How do I fix CVE-2026-64483?
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-2026-64483 being exploited?
There is no known exploitation of CVE-2026-64483 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-64483, DEBIAN-CVE-2026-64483, GHSA-j22x-mh97-frw2, ROOT-OS-UBUNTU-2204-CVE-2026-64483, UBUNTU-CVE-2026-64483.