CVE-2026-98553 autofs: fix sbi->pipe file reference leak in autofs_kill_sb()
A resource leak in the Linux kernel autofs module allows local attackers to exhaust system memory, leading to denial of service.
- 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-2026-98553?
CVE-2026-98553 is a denial of service 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:
autofs: fix sbi->pipe file reference leak in autofs_kill_sb()
When autofs_fill_super() fails before clearing AUTOFS_SBI_CATATONIC (for example, when find_get_pid() fails on an invalid pgrp mount option, or when an fs_context is closed before mounting), deactivate_locked_super() invokes autofs_kill_sb() -> autofs_catatonic_mode(sbi).
Because AUTOFS_SBI_CATATONIC is still set in sbi->flags, autofs_catatonic_mode() returns early without calling fput(sbi->pipe), permanently leaking the pipe struct file reference.
Explicitly release sbi->pipe in autofs_kill_sb() if it is still non-NULL after autofs_catatonic_mode().
Which versions are affected by CVE-2026-98553?
How do I fix CVE-2026-98553?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-98553 being exploited?
There is no known exploitation of CVE-2026-98553 in the wild and no public exploit code.
Sources
Also known as AZL-108863, BELL-CVE-2026-98553, DEBIAN-CVE-2026-98553, GHSA-j44w-wp8g-33m4, UBUNTU-CVE-2026-98553.