CVE-2026-89716 zram: validate deflate params

Not scored Published 11 Sep 2026 Updated 19 Oct 2026

A local attacker can trigger a kernel crash by providing invalid deflate parameters to the zram module, causing a 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-2026-89716?

CVE-2026-89716 is a denial of service vulnerability in Linux, published on 11 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:

zram: validate deflate params

We must validate user-supplied deflate winbits before we pass it to zlib_deflate_workspacesize(), which triggers BUG_ON() if winbits value is outside of valid ranges.

Which versions are affected by CVE-2026-89716?

How do I fix CVE-2026-89716?

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-2026-89716 being exploited?

There is no known exploitation of CVE-2026-89716 in the wild and no public exploit code.

Sources

Also known as BELL-CVE-2026-89716, DEBIAN-CVE-2026-89716, GHSA-3v8m-qpf5-mp53, UBUNTU-CVE-2026-89716.