CVE-2026-89794 ksmbd: zero pipe read compound padding
An attacker can read uninitialized kernel heap memory via ksmbd pipe read compound padding, potentially exposing sensitive data.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89794?
CVE-2026-89794 is a vulnerability in Linux, published on 16 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: zero pipe read compound padding
Compound response handling extends the last response iov to an eight-byte boundary.
smb2_read_pipe() allocates only the payload size, so the alignment padding can expose up to seven bytes of uninitialized kernel heap memory.
Allocate the aligned size and clear the unused tail before pinning the response buffer.
Which versions are affected by CVE-2026-89794?
How do I fix CVE-2026-89794?
Apply the vendor's patch.
Is CVE-2026-89794 being exploited?
There is no known exploitation of CVE-2026-89794 in the wild and no public exploit code.
Sources
Also known as AZL-101355, BELL-CVE-2026-89794, DEBIAN-CVE-2026-89794, GHSA-69w5-4c2f-pfhh, UBUNTU-CVE-2026-89794.