CVE-2026-89843 scsi: qla2xxx: Zero-init bsg stack buffers to avoid info leak
A local attacker can read uninitialized kernel stack memory via the qla2xxx SCSI driver, potentially exposing sensitive data.
- 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-2026-89843?
CVE-2026-89843 is a vulnerability in Linux, published on 16 Sep 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:
scsi: qla2xxx: Zero-init bsg stack buffers to avoid info leak
Several bsg handlers stage their request/reply in an uninitialized 256-byte on-stack buffer (uint8_t bsg[DMA_POOL_SIZE]) and fill it via sg_copy_to_buffer(), which only copies as many bytes as the user-supplied request payload. When the request is shorter than the structure, the remainder of the buffer is left holding stale stack data.
qla2x00_read_fru_status() and qla2x00_read_i2c() then copy the full structure back to the reply payload with sg_copy_from_buffer(), leaking the uninitialized stack bytes to user space. The write/update paths do not copy the buffer back, but can feed uninitialized fields to the device.
Zero the stack buffer at declaration in all five handlers, mirroring the heap kzalloc() approach, so short requests can no longer expose stale memory.
Which versions are affected by CVE-2026-89843?
How do I fix CVE-2026-89843?
Apply the vendor's patch.
Is CVE-2026-89843 being exploited?
There is no known exploitation of CVE-2026-89843 in the wild and no public exploit code.
Sources
Also known as AZL-101598, BELL-CVE-2026-89843, DEBIAN-CVE-2026-89843, GHSA-x3rh-x4gx-m2j8, UBUNTU-CVE-2026-89843.